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2022-05-31Improve break-range's documentationPedro Alves1-7/+9
Change-Id: Iac26e1d2e7d8dc8a7d9516e6bdcc5c3fc4af45c8
2022-05-31Explicitly mention yet-unloaded shared libraries in location spec examplesPedro Alves1-2/+4
Change-Id: I05639ddb3bf620c7297b57ed286adc3aa926b7b6
2022-05-30gdb/manual: Introduce location specsPedro Alves3-191/+305
The current "Specify Location" section of the GDB manual starts with: "Several @value{GDBN} commands accept arguments that specify a location of your program's code." And then, such commands are documented as taking a "location" argument. For example, here's a representative subset: @item break @var{location} @item clear @var{location} @item until @var{location} @item list @var{location} @item edit @var{location} @itemx info line @var{location} @item info macros @var{location} @item trace @var{location} @item info scope @var{location} @item maint agent @r{[}-at @var{location}@r{,}@r{]} @var{expression} The issue here is that "location" isn't really correct for most of these commands. Instead, the "location" argument is really a placeholder that represent an umbrella term for all of the "linespecs", "explicit location", and "address location" input formats. GDB parses these and then finds the actual code locations (plural) in the program that match. For example, a "location" specified like "-function func" will actually match all the code locations in the program that correspond to the address/file/lineno of all the functions named "func" in all the loaded programs and shared libraries of all the inferiors. A location specified like "-function func -label lab" matches all the addresses of C labels named "lab" in all functions named "func". Etc. This means that several of the commands that claim they accept a "location", actually end up working with multiple locations, and the manual doesn't explain that all that well. In some cases, the command will work with all the resolved locations. In other cases, the command aborts with an error if the location specification resolves to multiple locations in the program. In other cases, GDB just arbitrarily and silently picks whatever is the first resolved code location (which sounds like should be improved). To clarify this, I propose we use the term "Location Specification", with shorthand "locaction spec", when we're talking about the user input, the argument or arguments that is/are passed to commands to instruct GDB how to find locations of interest. This is distinct from the actual code locations in the program, which are what GDB finds based on the user-specified location spec. Then use "location specification or the shorter "location spec" thoughout instead of "location" when we're talking about the user input. Thus, this commit does the following: - renames the "Specify Location" section of the manual to "Location Specifications". - It then introduces the term "Location Specification", with corresponding shorthand "location spec", as something distinct from an actual code location in the program. It explains what a concrete code location is. It explains that a location specification may be incomplete, and that may match multiple code locations in the program, or no code location at all. It gives examples. Some pre-existing examples were moved from the "Set Breaks" section, and a few new ones that didn't exist yet were added. I think it is better to have these centralized in this "Location Specification" section, since all the other commands that accept a location spec have an xref that points there. - Goes through the manual, and where "@var{location}" was used for a command argument, updated it to say "@var{locspec}" instead. At the same time, tweaks the description of the affected commands to describe what happens when the location spec resolves to more than one location. Most commands just did not say anything about that. One command -- "maint agent -at @var{location}" -- currently says it accepts a "location", suggesting it can accept address and explicit locations too, but that's incorrect. In reality, it only accepts linespecs, so fix it accordingly. One MI command -- "-trace-find line" -- currently says it accepts a "line specification", but it can accept address and explicit locations too, so fix it accordingly. Special thanks goes to Eli Zaretskii for reviews and rewording suggestions. Change-Id: Ic42ad8565e79ca67bfebb22cbb4794ea816fd08b
2022-05-25Show enabled locations with disabled breakpoint parent as "y-"Pedro Alves1-0/+13
Currently, breakpoint locations that are enabled while their parent breakpoint is disabled are displayed with "y" in the Enb colum of "info breakpoints": (gdb) info breakpoints Num Type Disp Enb Address What 1 breakpoint keep n <MULTIPLE> 1.1 y 0x00000000000011b6 in ... 1.2 y 0x00000000000011c2 in ... 1.3 n 0x00000000000011ce in ... Such locations won't trigger a break, so to avoid confusion, show "y-" instead. For example: (gdb) info breakpoints Num Type Disp Enb Address What 1 breakpoint keep n <MULTIPLE> 1.1 y- 0x00000000000011b6 in ... 1.2 y- 0x00000000000011c2 in ... 1.3 n 0x00000000000011ce in ... The "-" sign is inspired on how the TUI represents breakpoints on the left side of the source window, with "b-" for a disabled breakpoint. Change-Id: I9952313743c51bf21b4b380c72360ef7d4396a09
2022-05-20Remove obsolete text from documentationTom Tromey1-3/+0
The documentation says that -enable-pretty-printing is experimental in 7.0 and may change -- that's long enough ago that I think we can say that this text is no longer correct or useful.
2022-05-19gdb/doc: use @value{GDBP} in 'info pretty-printer' exampleAndrew Burgess1-8/+8
Update the 'info pretty-printer' example in the manual to make use of @value{GDBP} instead of hard-coding '(gdb)'.
2022-05-19gdb/doc: make use of group/end group in 'info pretty-printers' exampleAndrew Burgess1-0/+10
The 'info pretty-printers' example is pretty long and consists of many commands and their output. Currently, when the pdf manual is generated this example spans a page-break, with the page-break falling part way through some example output from GDB. This commit breaks up the example using @group .... @end group, within each group is a single GDB command and all its output. Now, when the pdf manual is created, the page-break is placed after the output of one GDB command, and before the subsequent command, this looks much nicer.
2022-05-19gdb/doc: fix inconsistent info pretty-printer exampleNikolaos Chatzikonstantinou1-3/+1
The example for 'info pretty-printer' in the manual passes an object-regexp in some cases, but presents output as though no object-regexp was passed. This commit fixes the two mistakes, in one case, fixing the output to filter based on object-regexp, and in the other, to remove the object-regexp from the command and leave all the output.
2022-05-17Fix typo in info pageNikolaos Chatzikonstantinou1-1/+1
2022-05-16gdb: Fix typo in last change in gdb.texinfoEli Zaretskii1-1/+1
2022-05-16gdb: Document the 'metadata' styling in GDB displays.Eli Zaretskii1-0/+10
The 'metadata' styling was never documented in the GDB manual. This fills that gap.
2022-04-27gdb/arm: Extend arm_m_addr_is_magic to support FNC_RETURN, add ↵Christophe Lyon1-0/+10
unwind-secure-frames command This patch makes use of the support for several stack pointers introduced by the previous patch to switch between them as needed during unwinding. It introduces a new 'unwind-secure-frames' arm command to enable/disable mode switching during unwinding. It is enabled by default. It has been tested using an STM32L5 board (with cortex-m33) and the sample applications shipped with the STM32Cube development environment: GTZC_TZSC_MPCBB_TrustZone in STM32CubeL5/Projects/NUCLEO-L552ZE-Q/Examples/GTZC. The test consisted in setting breakpoints in various places and check that the backtrace is correct: SecureFault_Callback (Non-secure mode), __gnu_cmse_nonsecure_call (before and after the vpush instruction), SecureFault_Handler (Secure mode). This implies that we tested only some parts of this patch (only MSP* were used), but remaining parts seem reasonable. Signed-off-by: Torbjörn Svensson <torbjorn.svensson@st.com> Signed-off-by: Christophe Lyon <christophe.lyon@foss.st.com> Signed-off-by: Christophe Lyon <christophe.lyon@arm.com>
2022-04-14Reorganize Python events documentationTom Tromey1-29/+33
This slightly reorganizes the Python events documentation. It hoists the "ThreadEvent" text out of the list of events, where it seemed to be misplaced. It tidies the formatting a little bit (adding some vertical space for easier reading in info), fixes a typo, adds some missing commas, and fixes an incorrect reference to NewInferiorEvent.
2022-04-12Remove "Ada Settings" node from the manualTom Tromey1-32/+0
A while back, I sent a patch to unify the Ada varsize-limit setting with the more generic max-value-size: https://sourceware.org/pipermail/gdb-patches/2021-September/182004.html However, it turns out I somehow neglected to send part of the patch. Internally, I also removed the "Ada Settings" node from the manual, as it only documents the obsolete setting. This patch removes this text.
2022-04-11gdb/doc: add section about Fortran intrinsic functions and typesNils-Christian Kempke1-10/+133
The earlier version of this document had no sections about the available Fortran intrinsic functions or the Fortran builtin types. I added two sections 'Fortran intrinsics' and 'Fortran types' to document the available Fortran language features. The subsection 'Fortran Defaults' has been integrated into the Fortran subsection.
2022-04-06Enable ARMv8.1-m PACBTI supportLuis Machado1-0/+7
This set of changes enable support for the ARMv8.1-m PACBTI extensions [1]. The goal of the PACBTI extensions is similar in scope to that of a-profile PAC/BTI (aarch64 only), but the underlying implementation is different. One important difference is that the pointer authentication code is stored in a separate register, thus we don't need to mask/unmask the return address from a function in order to produce a correct backtrace. The patch introduces the following modifications: - Extend the prologue analyser for 32-bit ARM to handle some instructions from ARMv8.1-m PACBTI: pac, aut, pacg, autg and bti. Also keep track of return address signing/authentication instructions. - Adds code to identify object file attributes that indicate the presence of ARMv8.1-m PACBTI (Tag_PAC_extension, Tag_BTI_extension, Tag_PACRET_use and Tag_BTI_use). - Adds support for DWARF pseudo-register RA_AUTH_CODE, as described in the aadwarf32 [2]. - Extends the dwarf unwinder to track the value of RA_AUTH_CODE. - Decorates backtraces with the "[PAC]" identifier when a frame has signed the return address. - Makes GDB aware of a new XML feature "org.gnu.gdb.arm.m-profile-pacbti". This feature is not included as an XML file on GDB's side because it is only supported for bare metal targets. - Additional documentation. [1] https://community.arm.com/arm-community-blogs/b/architectures-and-processors-blog/posts/armv8-1-m-pointer-authentication-and-branch-target-identification-extension [2] https://github.com/ARM-software/abi-aa/blob/main/aadwarf32/aadwarf32.rst
2022-04-05Fix qRcmd error code parsingLuis Machado1-1/+2
Someone at IRC spotted a bug in qRcmd handling. This looks like an oversight or it is that way for historical reasons. The code in gdb/remote.c:remote_target::rcmd uses isdigit instead of isxdigit. One could argue that we are expecting decimal numbers, but further below we use fromhex (). Update the function to use isxdigit instead and also update the documentation. I see there are lots of other cases of undocumented number format for error messages, mostly described as NN instead of nn. For now I'll just update this particular function.
2022-04-04gdb: Add maint set ignore-prologue-end-flagLancelot SIX1-0/+13
The previous patch added support for the DWARF prologue-end flag in line table. This flag can be used by DWARF producers to indicate where to place breakpoints past a function prologue. However, this takes precedence over prologue analyzers. So if we have to debug a program with erroneous debug information, the overall debugging experience will be degraded. This commit proposes to add a maintenance command to instruct GDB to ignore the prologue_end flag. Tested on x86_64-gnu-linux. Change-Id: Idda6d1b96ba887f4af555b43d9923261b9cc6f82
2022-04-04gdb: Add support for DW_LNS_set_prologue_end in line-tableLancelot SIX1-0/+27
Add support for DW_LNS_set_prologue_end when building line-tables. This attribute can be set by the compiler to indicate that an instruction is an adequate place to set a breakpoint just after the prologue of a function. The compiler might set multiple prologue_end, but considering how current skip_prologue_using_sal works, this commit modifies it to accept the first instruction with this marker (if any) to be the place where a breakpoint should be placed to be at the end of the prologue. The need for this support came from a problematic usecase generated by hipcc (i.e. clang). The problem is as follows: There's a function (lets call it foo) which covers PC from 0xa800 to 0xa950. The body of foo begins with a call to an inlined function, covering from 0xa800 to 0xa94c. The issue is that when placing a breakpoint at 'foo', GDB inserts the breakpoint at 0xa818. The 0x18 offset is what GDB thinks is foo's first address past the prologue. Later, when hitting the breakpoint, GDB reports the stop within the inlined function because the PC falls in its range while the user expects to stop in FOO. Looking at the line-table for this location, we have: INDEX LINE ADDRESS IS-STMT [...] 14 293 0x000000000000a66c Y 15 END 0x000000000000a6e0 Y 16 287 0x000000000000a800 Y 17 END 0x000000000000a818 Y 18 287 0x000000000000a824 Y [...] For comparison, let's look at llvm-dwarfdump's output for this CU: Address Line Column File ISA Discriminator Flags ------------------ ------ ------ ------ --- ------------- ------------- [...] 0x000000000000a66c 293 12 2 0 0 is_stmt 0x000000000000a6e0 96 43 82 0 0 is_stmt 0x000000000000a6f8 102 18 82 0 0 is_stmt 0x000000000000a70c 102 24 82 0 0 0x000000000000a710 102 18 82 0 0 0x000000000000a72c 101 16 82 0 0 is_stmt 0x000000000000a73c 2915 50 83 0 0 is_stmt 0x000000000000a74c 110 1 1 0 0 is_stmt 0x000000000000a750 110 1 1 0 0 is_stmt end_sequence 0x000000000000a800 107 0 1 0 0 is_stmt 0x000000000000a800 287 12 2 0 0 is_stmt prologue_end 0x000000000000a818 114 59 81 0 0 is_stmt 0x000000000000a824 287 12 2 0 0 is_stmt 0x000000000000a828 100 58 82 0 0 is_stmt [...] The main difference we are interested in here is that llvm-dwarfdump's output tells us that 0xa800 is an adequate place to place a breakpoint past a function prologue. Since we know that foo covers from 0xa800 to 0xa94c, 0xa800 is the address at which the breakpoint should be placed if the user wants to break in foo. This commit proposes to add support for the prologue_end flag in the line-program processing. The processing of this prologue_end flag is made in skip_prologue_sal, before it calls gdbarch_skip_prologue_noexcept. The intent is that if the compiler gave information on where the prologue ends, we should use this information and not try to rely on architecture dependent logic to guess it. The testsuite have been executed using this patch on GNU/Linux x86_64. Testcases have been compiled with both gcc/g++ (verison 9.4.0) and clang/clang++ (version 10.0.0) since at the time of writing GCC does not set the prologue_end marker. Tests done with GCC 11.2.0 (not over the entire testsuite) show that it does not emit this flag either. No regression have been observed with GCC or Clang. Note that when using Clang, this patch fixes a failure in gdb.opt/inline-small-func.exp. Change-Id: I720449a8a9b2e1fb45b54c6095d3b1e9da9152f8
2022-04-03gdb/tui: add a tui debugging flagAndrew Burgess1-0/+11
This commit adds 'set debug tui on|off' and 'show debug tui'. This commit adds the control variable, and the printing macros in tui/tui.h. I've then added some uses of these in tui.c and tui-layout.c. To help produce more useful debug output in tui-layout.c, I've added some helper member functions in the class tui_layout_split, and also moved the size_info struct out of tui_layout_split::apply into the tui_layout_split class. If tui debug is not turned on, then there should be no user visible changes after this commit. One thing to note is that, due to the way that the tui terminal is often cleared, the only way I've found this useful is when I do: (gdb) tui enable (gdb) set logging file /path/to/file (gdb) set logging debugredirect on (gdb) set logging enable on Additionally, gdb has some quirks when it comes to setting up logging redirect and switching interpreters. Thus, the above only really works if the logging is enabled after the tui is enabled, and disabled again before the tui is disabled. Enabling logging and switching interpreters can cause undefined results, including crashes. This is an existing bug in gdb[1], and has nothing directly to do with tui debug, but it is worth mentioning here I think. [1] https://sourceware.org/bugzilla/show_bug.cgi?id=28948
2022-04-03gdb/tui: add new 'tui window width' command and 'winwidth' aliasAndrew Burgess1-0/+22
This commit adds a new command 'tui window width', and an alias 'winwidth'. This command is equivalent to the old 'winheight' command (which was recently renamed 'tui window height'). Even though I recently moved the old tui commands under the tui namespace, and I would strongly encourage all new tui commands to be added as 'tui ....' only (users can create their own top-level aliases if they want), I'm breaking that suggestion here, and adding a 'winwidth' alias. Given that we already have 'winheight' and have done for years, it just didn't seem right to no have the matching 'winwidth'. You might notice in the test that the window resizing doesn't quite work right. I setup a horizontal layout, then grow and shrink the windows. At the end of the test the windows should be back to their original size... ... they are not. This isn't my fault, honest! GDB's window resizing is a little ... temperamental, and is prone to getting things slightly wrong during resizes, off by 1 type things. This is true for height resizing, as well as the new width resizing. Later patches in this series will rework the resizing algorithm, which should improve things in this area. For now, I'm happy that the width resizing is as good as the height resizing, given the existing quirks. For the docs side I include a paragraph that explains how multiple windows are required before the width can be adjusted. For completeness, I've added the same paragraph to the winheight description. With the predefined layouts this extra paragraph is not really needed for winheight, as there are always multiple windows on the screen. However, with custom layouts, this might not be true, so adding the paragraph seems like a good idea. As for the changes in gdb itself, I've mostly just taken the existing height adjustment code, changed the name to make it generic 'size' adjustment, and added a boolean flag to indicate if we are adjusting the width or the height.
2022-04-03gdb: move some commands into the tui namespaceAndrew Burgess1-5/+13
There are a lot of tui related commands that live in the top-level command name space, e.g. layout, focus, refresh, winheight. Having them at the top level means less typing for the user, which is good, but, I think, makes command discovery harder. In this commit, I propose moving all of the above mentioned commands into the tui namespace, so 'layout' becomes 'tui layout', etc. But I will then add aliases so that the old commands will still work, e.g. I'll make 'layout' an alias for 'tui layout'. The benefit I see in this work is that tui related commands can be more easily discovered by typing 'tui ' and then tab-completing. Also the "official" command is now a tui-sub-command, this is visible in, for example, the help output, e.g.: (gdb) help layout tui layout, layout Change the layout of windows. Usage: tui layout prev | next | LAYOUT-NAME List of tui layout subcommands: tui layout asm -- Apply the "asm" layout. tui layout next -- Apply the next TUI layout. tui layout prev -- Apply the previous TUI layout. tui layout regs -- Apply the TUI register layout. tui layout split -- Apply the "split" layout. tui layout src -- Apply the "src" layout. Which I think is a good thing, it makes it clearer that this is a tui command. I've added a NEWS entry and updated the docs to mention the new and old command names, with the new name being mentioned first.
2022-03-31Style URLs in GDB outputTom Tromey1-1/+1
I noticed that GDB will display URLs in a few spots. This changes them to be styled. Originally I thought I'd introduce a new "url" style, but there aren't many places to use this, so I just reused filename styling instead. This patch also changes the debuginfod URL list to be printed one URL per line. I think this is probably a bit easier to read.
2022-03-31Remove dbx modeTom Tromey1-3/+0
This patch removes gdb's dbx mode. Regression tested on x86-64 Fedora 34.
2022-03-23gdb/python: remove Python 2 supportSimon Marchi1-2/+0
New in this version: - Add a PY_MAJOR_VERSION check in configure.ac / AC_TRY_LIBPYTHON. If the user passes --with-python=python2, this will cause a configure failure saying that GDB only supports Python 3. Support for Python 2 is a maintenance burden for any patches touching Python support. Among others, the differences between Python 2 and 3 string and integer types are subtle. It requires a lot of effort and thinking to get something that behaves correctly on both. And that's if the author and reviewer of the patch even remember to test with Python 2. See this thread for an example: https://sourceware.org/pipermail/gdb-patches/2021-December/184260.html So, remove Python 2 support. Update the documentation to state that GDB can be built against Python 3 (as opposed to Python 2 or 3). Update all the spots that use: - sys.version_info - IS_PY3K - PY_MAJOR_VERSION - gdb_py_is_py3k ... to only keep the Python 3 portions and drop the use of some now-removed compatibility macros. I did not update the configure script more than just removing the explicit references to Python 2. We could maybe do more there, like check the Python version and reject it if that version is not supported. Otherwise (with this patch), things will only fail at compile time, so it won't really be clear to the user that they are trying to use an unsupported Python version. But I'm a bit lost in the configure code that checks for Python, so I kept that for later. Change-Id: I75b0f79c148afbe3c07ac664cfa9cade052c0c62
2022-03-22gdb/python: add gdb.format_address functionAndrew Burgess1-0/+54
Add a new function, gdb.format_address, which is a wrapper around GDB's print_address function. This method takes an address, and returns a string with the format: ADDRESS <SYMBOL+OFFSET> Where, ADDRESS is the original address, formatted as hexadecimal, SYMBOL is a symbol with an address lower than ADDRESS, and OFFSET is the offset from SYMBOL to ADDRESS in decimal. If there's no SYMBOL suitably close to ADDRESS then the <SYMBOL+OFFSET> part is not included. This is useful if a user wants to write a Python script that pretty-prints addresses, the user no longer needs to do manual symbol lookup, or worry about correctly formatting addresses. Additionally, there are some settings that effect how GDB picks SYMBOL, and whether the file name and line number should be included with the SYMBOL name, the gdb.format_address function ensures that the users Python script also benefits from these settings. The gdb.format_address by default selects SYMBOL from the current inferiors program space, and address is formatted using the architecture for the current inferior. However, a user can also explicitly pass a program space and architecture like this: gdb.format_address(ADDRESS, PROGRAM_SPACE, ARCHITECTURE) In order to format an address for a different inferior. Notes on the implementation: In py-arch.c I extended arch_object_to_gdbarch to add an assertion for the type of the PyObject being worked on. Prior to this commit all uses of arch_object_to_gdbarch were guaranteed to pass this function a gdb.Architecture object, but, with this commit, this might not be the case. So, with this commit I've made it a requirement that the PyObject be a gdb.Architecture, and this is checked with the assert. And in order that callers from other files can check if they have a gdb.Architecture object, I've added the new function gdbpy_is_architecture. In py-progspace.c I've added two new function, the first progspace_object_to_program_space, converts a PyObject of type gdb.Progspace to the associated program_space pointer, and gdbpy_is_progspace checks if a PyObject is a gdb.Progspace or not.
2022-03-16Reimplement array concatenation for Ada and DTom Tromey1-4/+1
This started as a patch to implement string concatenation for Ada. However, while working on this, I looked at how this code could possibly be called. It turns out there are only two users of concat_operation: Ada and D. So, in addition to implementing this for Ada, this patch rewrites value_concat, removing the odd "concatenate or repeat" semantics, which were completely unused. As Ada and D both seem to represent strings using TYPE_CODE_ARRAY, this removes the TYPE_CODE_STRING code from there as well.
2022-03-14gdb/python/mi: create MI commands using pythonAndrew Burgess1-8/+160
This commit allows a user to create custom MI commands using Python similarly to what is possible for Python CLI commands. A new subclass of mi_command is defined for Python MI commands, mi_command_py. A new file, gdb/python/py-micmd.c contains the logic for Python MI commands. This commit is based on work linked too from this mailing list thread: https://sourceware.org/pipermail/gdb/2021-November/049774.html Which has also been previously posted to the mailing list here: https://sourceware.org/pipermail/gdb-patches/2019-May/158010.html And was recently reposted here: https://sourceware.org/pipermail/gdb-patches/2022-January/185190.html The version in this patch takes some core code from the previously posted patches, but also has some significant differences, especially after the feedback given here: https://sourceware.org/pipermail/gdb-patches/2022-February/185767.html A new MI command can be implemented in Python like this: class echo_args(gdb.MICommand): def invoke(self, args): return { 'args': args } echo_args("-echo-args") The 'args' parameter (to the invoke method) is a list containing (almost) all command line arguments passed to the MI command (--thread and --frame are handled before the Python code is called, and removed from the args list). This list can be empty if the MI command was passed no arguments. When used within gdb the above command produced output like this: (gdb) -echo-args a b c ^done,args=["a","b","c"] (gdb) The 'invoke' method of the new command must return a dictionary. The keys of this dictionary are then used as the field names in the mi command output (e.g. 'args' in the above). The values of the result returned by invoke can be dictionaries, lists, iterators, or an object that can be converted to a string. These are processed recursively to create the mi output. And so, this is valid: class new_command(gdb.MICommand): def invoke(self,args): return { 'result_one': { 'abc': 123, 'def': 'Hello' }, 'result_two': [ { 'a': 1, 'b': 2 }, { 'c': 3, 'd': 4 } ] } Which produces output like: (gdb) -new-command ^done,result_one={abc="123",def="Hello"},result_two=[{a="1",b="2"},{c="3",d="4"}] (gdb) I have required that the fields names used in mi result output must match the regexp: "^[a-zA-Z][-_a-zA-Z0-9]*$" (without the quotes). This restriction was never written down anywhere before, but seems sensible to me, and we can always loosen this rule later if it proves to be a problem. Much harder to try and add a restriction later, once people are already using the API. What follows are some details about how this implementation differs from the original patch that was posted to the mailing list. In this patch, I have changed how the lifetime of the Python gdb.MICommand objects is managed. In the original patch, these object were kept alive by an owned reference within the mi_command_py object. As such, the Python object would not be deleted until the mi_command_py object itself was deleted. This caused a problem, the mi_command_py were held in the global mi command table (in mi/mi-cmds.c), which, as a global, was not cleared until program shutdown. By this point the Python interpreter has already been shutdown. Attempting to delete the mi_command_py object at this point was causing GDB to try and invoke Python code after finalising the Python interpreter, and we would crash. To work around this problem, the original patch added code in python/python.c that would search the mi command table, and delete the mi_command_py objects before the Python environment was finalised. In contrast, in this patch, I have added a new global dictionary to the gdb module, gdb._mi_commands. We already have several such global data stores related to pretty printers, and frame unwinders. The MICommand objects are placed into the new gdb.mi_commands dictionary, and it is this reference that keeps the objects alive. When GDB's Python interpreter is shut down gdb._mi_commands is deleted, and any MICommand objects within it are deleted at this point. This change avoids having to make the mi_cmd_table global, and walk over it from within GDB's python related code. This patch handles command redefinition entirely within GDB's python code, though this does impose one small restriction which is not present in the original code (detailed below), I don't think this is a big issue. However, the original patch relied on being able to finish executing the mi_command::do_invoke member function after the mi_command object had been deleted. Though continuing to execute a member function after an object is deleted is well defined, it is also (IMHO) risky, its too easy for someone to later add a use of the object without realising that the object might sometimes, have been deleted. The new patch avoids this issue. The one restriction that is added to avoid this, is that an MICommand object can't be reinitialised with a different command name, so: (gdb) python cmd = MyMICommand("-abc") (gdb) python cmd.__init__("-def") can't reinitialize object with a different command name This feels like a pretty weird edge case, and I'm happy to live with this restriction. I have also changed how the memory is managed for the command name. In the most recently posted patch series, the command name is moved into a subclass of mi_command, the python mi_command_py, which inherits from mi_command is then free to use a smart pointer to manage the memory for the name. In this patch, I leave the mi_command class unchanged, and instead hold the memory for the name within the Python object, as the lifetime of the Python object always exceeds the c++ object stored in the mi_cmd_table. This adds a little more complexity in py-micmd.c, but leaves the mi_command class nice and simple. Next, this patch adds some extra functionality, there's a MICommand.name read-only attribute containing the name of the command, and a read-write MICommand.installed attribute that can be used to install (make the command available for use) and uninstall (remove the command from the mi_cmd_table so it can't be used) the command. This attribute will be automatically updated if a second command replaces an earlier command. This patch adds additional error handling, and makes more use the gdbpy_handle_exception function. Co-Authored-By: Jan Vrany <jan.vrany@labware.com>
2022-03-10Change how "print/x" displays floating-point valueTom Tromey1-13/+15
Currently, "print/x" will display a floating-point value by first casting it to an integer type. This yields weird results like: (gdb) print/x 1.5 $1 = 0x1 This has confused users multiple times -- see PR gdb/16242, where there are several dups. I've also seen some confusion from this internally at AdaCore. The manual says: 'x' Regard the bits of the value as an integer, and print the integer in hexadecimal. ... which seems more useful. So, perhaps what happened is that this was incorrectly implemented (or maybe correctly implemented and then regressed, as there don't seem to be any tests). This patch fixes the bug. There was a previous discussion where we agreed to preserve the old behavior: https://sourceware.org/legacy-ml/gdb-patches/2017-06/msg00314.html However, I think it makes more sense to follow the manual. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=16242
2022-03-09* gdb/doc/gdb.texinfo (Requirements): Fix a typo.Christina Schimpe1-1/+1
Copyright-paperwork-exempt: yes
2022-03-07gdb/python: add Type.is_signed propertyAndrew Burgess1-0/+10
Add a new read-only property, Type.is_signed, which is True for signed types, and False otherwise. This property should only be read on types for which Type.is_scalar is true, attempting to read this property for non-scalar types will raise a ValueError. I chose 'is_signed' rather than 'is_unsigned' in order to match the existing Architecture.integer_type method, which takes a 'signed' parameter. As far as I could find, that was the only existing signed/unsigned selector in the Python API, so it seemed reasonable to stay consistent.
2022-03-07gdb/python: add Type.is_scalar propertyAndrew Burgess1-0/+6
Add a new read-only property which is True for scalar types, otherwise, it's False.
2022-03-07gdb/mi: add --no-connection to MI -add-inferior commandAndrew Burgess1-4/+35
Following on from the previous commit, where the -add-inferior command now uses the same connection as the current inferior, this commit adds a --no-connection option to -add-inferior. This new option matches the existing option of the same name for the CLI version of add-inferior; the new inferior is created with no connection. I've added a new 'connection' field to the MI output of -add-inferior, which includes the connection number and short name. I haven't included the longer description field, this is the MI after all. My expectation would be that if the frontend wanted to display all the connection details then this would be looked up from 'info connection' (or the MI equivalent if/when such a command is added). The existing -add-inferior tests are updated, as are the docs.
2022-03-07Implement real literal extension for AdaTom Tromey1-0/+16
Sometimes it is convenient to be able to specify the exact bits of a floating-point literal. For example, you may want to set a floating-point register to a denormalized value, or to a particular NaN. In C, you can do this by combining the "{}" cast with an array literal, like: (gdb) p {double}{0x576488BDD2AE9FFE} $1 = 9.8765449999999996e+112 This patch adds a somewhat similar idea to Ada. It extends the lexer to allow "l" and "f" suffixes in a based literal. The "f" indicates a floating-point literal, and the "l"s control the size of the floating-point type. Note that this differs from Ada's based real literals. I believe those can also be used to control the bits of a floating-point value, but they are a bit more cumbersome to use (simplest is binary but that's also very lengthy). Also, these aren't implemented in GDB. I chose not to allow this extension to work with based integer literals with exponents. That didn't seem very useful.
2022-03-07Handle non-ASCII identifiers in AdaTom Tromey1-0/+23
Ada allows non-ASCII identifiers, and GNAT supports several such encodings. This patch adds the corresponding support to gdb. GNAT encodes non-ASCII characters using special symbol names. For character sets like Latin-1, where all characters are a single byte, it uses a "U" followed by the hex for the character. So, for example, thorn would be encoded as "Ufe" (0xFE being lower case thorn). For wider characters, despite what the manual says (it claims Shift-JIS and EUC can be used), in practice recent versions only support Unicode. Here, characters in the base plane are represented using "Wxxxx" and characters outside the base plane using "WWxxxxxxxx". GNAT has some further quirks here. Ada is case-insensitive, and GNAT emits symbols that have been case-folded. For characters in ASCII, and for all characters in non-Unicode character sets, lower case is used. For Unicode, however, characters that fit in a single byte are converted to lower case, but all others are converted to upper case. Furthermore, there is a bug in GNAT where two symbols that differ only in the case of "Y WITH DIAERESIS" (and potentially others, I did not check exhaustively) can be used in one program. I chose to omit handling this case from gdb, on the theory that it is hard to figure out the logic, and anyway if the bug is ever fixed, we'll regret having a heuristic. This patch introduces a new "ada source-charset" setting. It defaults to Latin-1, as that is GNAT's default. This setting controls how "U" characters are decoded -- W/WW are always handled as UTF-32. The ada_tag_name_from_tsd change is needed because this function will read memory from the inferior and interpret it -- and this caused an encoding failure on PPC when running a test that tries to read uninitialized memory. This patch implements its own UTF-32-based case folder. This avoids host platform quirks, and is relatively simple. A short Python program to generate the case-folding table is included. It simply relies on whatever version of Unicode is used by the host Python, which seems basically acceptable. Test cases for UTF-8, Latin-1, and Latin-3 are included. This exercises most of the new code paths, aside from Y WITH DIAERESIS as noted above.
2022-03-01Fix typo in the "alias" exampleTom Tromey1-1/+1
PR cli/17332, filed around 8 years ago, points out a typo in the docs -- in one example, the command and its output are obviously out of sync. This patch fixes it. I'm checking this in as obvious. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=17332
2022-02-28gdb/python: Add gdb.InferiorThread.details attributeAndrew Burgess2-0/+19
This adds a new read-only attribute gdb.InferiorThread.details, this attribute contains a string, the results of target_extra_thread_info for the thread, or None, if target_extra_thread_info returns nullptr. As the string returned by target_extra_thread_info is unstructured, this attribute is only really useful for echoing straight through to the user, but, if a user wants to write a command that displays the same, or a similar 'Thread Id' to the one seen in 'info threads', then they need access to this string. Given that the string produced by target_extra_thread_info varies by target, there's only minimal testing of this attribute, I check that the attribute can be accessed, and that the return value is either None, or a string.
2022-02-24Support template lookups in strncmp_iw_with_modeKeith Seitz1-0/+15
This patch adds support for wild template parameter list matches, similar to how ABI tags or function overloads are now handled. With this patch, users will be able to "gloss over" the details of matching template parameter lists. This is accomplished by adding (yet more) logic to strncmp_iw_with_mode to skip parameter lists if none is explicitly given by the user. Here's a simple example using gdb.linespec/cpls-ops.exp: Before ------ (gdb) ptype test_op_call type = struct test_op_call { public: void operator()(void); void operator()(int); void operator()(long); void operator()<int>(int *); } (gdb) b test_op_call::operator() Breakpoint 1 at 0x400583: test_op_call::operator(). (3 locations) (gdb) i b Num Type Disp Enb Address What 1 breakpoint keep y <MULTIPLE> 1.1 y 0x400583 in test_op_call::operator()(int) at cpls-ops.cc:43 1.2 y 0x40058e in test_op_call::operator()() at cpls-ops.cc:47 1.3 y 0x40059e in test_op_call::operator()(long) at cpls-ops.cc:51 The breakpoint at test_op_call::operator()<int> was never set. After ----- (gdb) b test_op_call::operator() Breakpoint 1 at 0x400583: test_op_call::operator(). (4 locations) (gdb) i b Num Type Disp Enb Address What 1 breakpoint keep y <MULTIPLE> 1.1 y 0x400583 in test_op_call::operator()(int) at cpls-ops.cc:43 1.2 y 0x40058e in test_op_call::operator()() at cpls-ops.cc:47 1.3 y 0x40059e in test_op_call::operator()(long) at cpls-ops.cc:51 1.4 y 0x4008d0 in test_op_call::operator()<int>(int*) at cpls-ops.cc:57 Similar to how scope lookups work, passing "-qualified" to the break command will cause a literal lookup of the symbol. In the example immediately above, this will cause GDB to only find the three non-template functions.
2022-02-14gdb: use python to colorize disassembler outputAndrew Burgess1-0/+15
This commit adds styling support to the disassembler output, as such two new commands are added to GDB: set style disassembler enabled on|off show style disassembler enabled In this commit I make use of the Python Pygments package to provide the styling. I did investigate making use of libsource-highlight, however, I found the highlighting results to be inferior to those of Pygments; only some mnemonics were highlighted, and highlighting of register names such as r9d and r8d (on x86-64) was incorrect. To enable disassembler highlighting via Pygments, I've added a new extension language hook, which is then implemented for Python. This hook is very similar to the existing hook for source code colorization. One possibly odd choice I made with the new hook is to pass a gdb.Architecture through, even though this is currently unused. The reason this argument is not used is that, currently, styling is performed identically for all architectures. However, even though the Python function used to perform styling of disassembly output is not part of any documented API, I don't want to close the door on a user overriding this function to provide architecture specific styling. To do this, the user would inevitably require access to the gdb.Architecture, and so I decided to add this field now. The styling is applied within gdb_disassembler::print_insn, to achieve this, gdb_disassembler now writes its output into a temporary buffer, styling is then applied to the contents of this buffer. Finally the gdb_disassembler buffer is copied out to its final destination stream. There's a new test to check that the disassembler output includes some escape sequences, though I don't check for specific colours; the precise colors will depend on which instructions are in the disassembler output, and, I guess, how pygments is configured. The only negative change with this commit is how we currently style addresses in GDB. Currently, when the disassembler wants to print an address, we call back into GDB, and GDB prints the address value using the `address` styling, and the symbol name using `function` styling. After this commit, if pygments is used, then all disassembler styling is done through pygments, and this include the address and symbol name parts of the disassembler output. I don't know how much of an issue this will be for people. There's already some precedent for this in GDB when we look at source styling. For example, function names in styled source listings are not styled using the `function` style, but instead, either GNU Source Highlight, or pygments gets to decide how the function name should be styled. If the Python pygments library is not present then GDB will continue to behave as it always has, the disassembler output is mostly unstyled, but the address and symbols are styled using the `address` and `function` styles, as they are today. However, if the user does `set style disassembler enabled off`, then all disassembler styling is switched off. This obviously covers the use of pygments, but also includes the minimal styling done by GDB when pygments is not available.
2022-02-11gdb: LoongArch: Add initial target description supportTiezhu Yang1-0/+10
This commit adds initial target description support for LoongArch. Signed-off-by: Zhensong Liu <liuzhensong@loongson.cn> Signed-off-by: Qing zhang <zhangqing@loongson.cn> Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
2022-02-07gdb/python: allow Value.format_string to return styled outputAndrew Burgess1-0/+10
Add a new argument to the gdb.Value.format_string method, 'styling'. This argument is False by default. When this argument is True, then the returned string can contain output styling escape sequences. When this argument is False, then the returned string will not contain any styling escape sequences. If the returned string is going to be printed to the user, then it is often nice to retain the GDB styling. For the testing, we need to adjust the TERM environment variable, as we do for all the styling tests. I'm now running all of the C tests in gdb.python/py-format-string.exp in an environment where styling could be generated, but only my new test should actually produce styled output, hopefully this will catch the case where a bug might cause format_string to always produce styled output.
2022-02-07gdb: add the 'set/show suppress-cli-notifications' commandTankut Baris Aktemur1-0/+69
GDB already has a flag to suppress printing notification events, such as thread and inferior context switches, on the CLI. This is used internally when executing commands. Make the flag available to the user via a new command. This is expected to be useful in scripts. For instance, suppose that when Inferior 1 gets to a certain state, you want to add and set up a new inferior using the commands below, but you also want to have a reduced/clean output. define do-setup printf "Setting up Inferior 2...\n" add-inferior -exec a.out inferior 2 break file.c:3 run inferior 1 printf "Done\n" end Currently, GDB prints (gdb) do-setup Setting up Inferior 2... [New inferior 2] Added inferior 2 on connection 1 (native) [Switching to inferior 2 [<null>] (/tmp/a.out)] Breakpoint 2 at 0x1155: file file.c, line 3. Thread 2.1 "a.out" hit Breakpoint 2, main () at file.c:3 3 return 0; [Switching to inferior 1 [process 7670] (/tmp/test)] [Switching to thread 1.1 (process 7670)] #0 main () at test.c:2 2 int a = 1; Done GDB's Python API make it possible to capture and return GDB's output, but this does not work for all the streams. In particular, CLI notification events are not captured: (gdb) python gdb.execute("do-setup", False, True) [Switching to inferior 2 [<null>] (/tmp/a.out)] Thread 2.1 "a.out" hit Breakpoint 2, main () at file.c:3 3 return 0; [Switching to inferior 1 [process 8263] (/tmp/test)] [Switching to thread 1.1 (process 8263)] #0 main () at test.c:2 2 int a = 1; You can use the new "set suppress-cli-notifications" command to suppress the output: (gdb) set suppress-cli-notifications on (gdb) do-setup Setting up Inferior 2... [New inferior 2] Added inferior 2 on connection 1 (native) Breakpoint 2 at 0x1155: file file.c, line 3. Done
2022-02-06gdb/doc: update docs for 'info win' and 'winheight' commandsAndrew Burgess1-6/+7
This started by noticing that the docs for 'winheight' are out of date, the docs currently give a specific list of possible window names. However, now that windows can be implemented in Python, it is not possible to list all possible names. I now link the user to a mechanism by which they can discover the valid names for themselves at run time (by using 'info win'). That, and the fact that gdb provides tab-completion of the name at the command line, feels good enough. Finally, I noticed that the docs for 'win info' don't explicitly say that the name of the window is given in the output. This could probably have been inferred, but given I'm now linking to this as a mechanism to find the window name, I'd prefer to mention that the name can be found in the output.
2022-01-26gdb/python: improve the auto help text for gdb.ParameterAndrew Burgess1-9/+32
This commit attempts to improve the help text that is generated for gdb.Parameter objects when the user fails to provide their own documentation. Documentation for a gdb.Parameter is currently pulled from two sources: the class documentation string, and the set_doc/show_doc class attributes. Thus, a fully documented parameter might look like this: class Param_All (gdb.Parameter): """This is the class documentation string.""" show_doc = "Show the state of this parameter" set_doc = "Set the state of this parameter" def get_set_string (self): val = "on" if (self.value == False): val = "off" return "Test Parameter has been set to " + val def __init__ (self, name): super (Param_All, self).__init__ (name, gdb.COMMAND_DATA, gdb.PARAM_BOOLEAN) self._value = True Param_All ('param-all') Then in GDB we see this: (gdb) help set param-all Set the state of this parameter This is the class documentation string. Which is fine. But, if the user skips both of the documentation parts like this: class Param_None (gdb.Parameter): def get_set_string (self): val = "on" if (self.value == False): val = "off" return "Test Parameter has been set to " + val def __init__ (self, name): super (Param_None, self).__init__ (name, gdb.COMMAND_DATA, gdb.PARAM_BOOLEAN) self._value = True Param_None ('param-none') Now in GDB we see this: (gdb) help set param-none This command is not documented. This command is not documented. That's not great, the duplicated text looks a bit weird. If we drop different parts we get different results. Here's what we get if the user drops the set_doc and show_doc attributes: (gdb) help set param-doc This command is not documented. This is the class documentation string. That kind of sucks, we say it's undocumented, then proceed to print the documentation. Finally, if we drop the class documentation but keep the set_doc and show_doc: (gdb) help set param-set-show Set the state of this parameter This command is not documented. That seems OK. So, I think there's room for improvement. With this patch, for the four cases above we now see this: # All values provided by the user, no change in this case: (gdb) help set param-all Set the state of this parameter This is the class documentation string. # Nothing provided by the user, the first string is now different: (gdb) help set param-none Set the current value of 'param-none'. This command is not documented. # Only the class documentation is provided, the first string is # changed as in the previous case: (gdb) help set param-doc Set the current value of 'param-doc'. This is the class documentation string. # Only the set_doc and show_doc are provided, this case is unchanged # from before the patch: (gdb) help set param-set-show Set the state of this parameter This command is not documented. The one place where this change might be considered a negative is when dealing with prefix commands. If we create a prefix command but don't supply the set_doc / show_doc strings, then this is what we saw before my patch: (gdb) python Param_None ('print param-none') (gdb) help set print set print, set pr, set p Generic command for setting how things print. List of set print subcommands: ... snip ... set print param-none -- This command is not documented. ... snip ... And after my patch: (gdb) python Param_None ('print param-none') (gdb) help set print set print, set pr, set p Generic command for setting how things print. List of set print subcommands: ... snip ... set print param-none -- Set the current value of 'print param-none'. ... snip ... This seems slightly less helpful than before, but I don't think its terrible. Additionally, I've changed what we print when the get_show_string method is not provided in Python. Back when gdb.Parameter was first added to GDB, we didn't provide a show function when registering the internal command object within GDB. As a result, GDB would make use of its "magic" mangling of the show_doc string to create a sentence that would display the current value (see deprecated_show_value_hack in cli/cli-setshow.c). However, when we added support for the get_show_string method to gdb.Parameter, there was an attempt to maintain backward compatibility by displaying the show_doc string with the current value appended, see get_show_value in py-param.c. Unfortunately, this isn't anywhere close to what deprecated_show_value_hack does, and the results are pretty poor, for example, this is GDB before my patch: (gdb) show param-none This command is not documented. off I think we can all agree that this is pretty bad. After my patch, we how show this: (gdb) show param-none The current value of 'param-none' is "off". Which at least is a real sentence, even if it's not very informative. This patch does change the way that the Python API behaves slightly, but only in the cases when the user has missed providing GDB with some information. In most cases I think the new behaviour is a lot better, there's the one case (noted above) which is a bit iffy, but I think is still OK. I've updated the existing gdb.python/py-parameter.exp test to cover the modified behaviour. Finally, I've updated the documentation to (I hope) make it clearer how the various bits of help text come together.
2022-01-26gdb/python: add gdb.history_count functionAndrew Burgess1-0/+5
Add a new function gdb.history_count to the Python api, this function returns an integer, the number of items in GDB's value history. This is useful if you want to pull items from the history by their absolute number, for example, if you wanted to show a complete history list. Previously we could figure out how many items are in the history list by trying to fetch the items, and then catching the exception when the item is not available, but having this function seems nicer.
2022-01-26Add a way to temporarily set a gdb parameter from PythonTom Tromey1-0/+26
It's sometimes useful to temporarily set some gdb parameter from Python. Now that the 'endian' crash is fixed, and now that the current language is no longer captured by the Python layer, it seems reasonable to add a helper function for this situation. This adds a new gdb.with_parameter function. This creates a context manager which temporarily sets some parameter to a specified value. The old value is restored when the context is exited. This is most useful with the Python "with" statement: with gdb.with_parameter('language', 'ada'): ... do Ada stuff This also adds a simple function to set a parameter, gdb.set_parameter, as suggested by Andrew. This is PR python/10790. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=10790
2022-01-24gdb/doc: improve description for Window.click on Python TUI windowsAndrew Burgess1-3/+3
The description of the Window.click method doesn't mention where the coordinates are anchored (it's the top left corner). This minor tweak just mentions this point.
2022-01-21gdb/doc: fill in two missing @rAndrew Burgess1-2/+2
I noticed two places in the docs where we appear to be missing @r. makeinfo seems to do the correct things despite these being missing (at least, I couldn't see any difference in the pdf or info output), but it doesn't hurt to have the @r in place.
2022-01-12gdb/python: add gdb.host_charset functionAndrew Burgess1-0/+8
We already have gdb.target_charset and gdb.target_wide_charset. This commit adds gdb.host_charset along the same lines.
2022-01-12gdb: add 'maint set/show gnu-source-highlight enabled' commandAndrew Burgess1-0/+19
In a later commit I want to address an issue with the Python pygments based code styling solution. As this approach is only used when the GNU Source Highlight library is not available, testing bugs in this area can be annoying, as it requires GDB to be rebuilt with use of GNU Source Highlight disabled. This commit adds a pair of new maintenance commands: maintenance set gnu-source-highlight enabled on|off maintenance show gnu-source-highlight enabled these commands can be used to disable use of the GNU Source Highlight library, allowing me, in a later commit, to easily test bugs that would otherwise be masked by GNU Source Highlight being used. I made this a maintenance command, rather than a general purpose command, as it didn't seem like this was something a general user would need to adjust. We can always convert the maintenance command to a general command later if needed. There's no test for this here, but this feature will be used in a later commit.