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2022-11-07configure: require libzstd >= 1.4.0Christophe Lyon1-10/+10
gas uses ZSTD_compressStream2 which is only available with libzstd >= 1.4.0, leading to build errors when an older version is installed. This patch updates the check libzstd presence to check its version is >= 1.4.0. However, since gas seems to be the only component requiring such a recent version this may imply that we disable ZSTD support for all components although some would still benefit from an older version. I ran 'autoreconf -f' in all directories containing a configure.ac file, using vanilla autoconf-2.69 and automake-1.15.1. I noticed several errors from autoheader in readline, as well as warnings in intl, but they are unrelated to this patch. This should fix some of the buildbots. OK for trunk? Thanks, Christophe
2022-09-26libctf: Add ZSTD_LIBS to LIBS so that ac_cv_libctf_bfd_elf can be trueFangrui Song5-6/+280
2022-08-01libctf: Avoid use of uninitialised variablesAlan Modra1-6/+10
* ctf-link.c (ctf_link_add_ctf_internal): Don't free uninitialised pointers.
2022-07-08Add markers for 2.39 branchNick Clifton1-0/+4
2022-06-21libctf: tests: prune warnings from compiler outputNick Alcock2-6/+6
We were failing to call prune_warnings appropriately, leading to false-positive test failures on some platforms (observed on sparclinux). libctf/ChangeLog: * testsuite/lib/ctf-lib.exp: Prune warnings from compiler and linker output. * testsuite/libctf-regression/libctf-repeat-cu.exp: Likewise, and ar output too.
2022-06-21libctf: avoid mingw warningNick Alcock1-1/+1
A missing paren led to an intended cast to avoid dependence on the size of size_t in one argument of ctf_err_warn applying to the wrong type by mistake. libctf/ChangeLog: * ctf-serialize.c (ctf_write_mem): Fix cast.
2022-06-21libctf: fix linking together multiple objects derived from the same sourceNick Alcock8-33/+280
Right now, if you compile the same .c input repeatedly with CTF enabled and different compilation flags, then arrange to link all of these together, then things misbehave in various ways. libctf may conflate either inputs (if the .o files have the same name, say if they are stored in different .a archives), or per-CU outputs when conflicting types are found: the latter can lead to entirely spurious errors when it tries to produce multiple per-CU outputs with the same name (discarding all but the last, but then looking for types in the earlier ones which have just been thrown away). Fixing this is multi-pronged. Both inputs and outputs need to be differentiated in the hashtables libctf keeps them in: inputs with the same cuname and filename need to be considered distinct as long as they have different associated CTF dicts, and per-CU outputs need to be considered distinct as long as they have different associated input dicts. Right now there is nothing tying the two together other than the CU name: fix this by introducing a new field in the ctf_dict_t named ctf_link_in_out, which (for input dicts) points to the associated per-CU output dict (if any), and for output dicts points to the associated input dict. At creation time the name used is completely arbitrary: it's only important that it be distinct if CTF dicts are distinct. So, when a clash is found, adjust the CU name by sticking the number of elements in the input on the end. At output time, the CU name will appear in the linked object, so it matters a little more that it look slightly less ugly: in conflicting cases, append an incrementing integer, starting at 0. This naming scheme is not very helpful, but it's hard to see what else we can do. The input .o name may be the same. The input .a name is not even visible to ctf_link, and even *that* might be the same, because .a's can contain many members with the same name, all of which participate in the link. All we really know is that the two have distinct dictionaries with distinct types in them, and at least this way they are all represented, any any symbols, variables etc referring to those types are accurately stored. (As a side-effect this also fixes a use-after-free and double-free when errors are found during variable or symbol emission.) Use the opportunity to prevent a couple of sources of problems, to wit changing the active CU mappings when a link has already been done (no effect on ld, which doesn't use CU mappings at all), and causing multiple consecutive ctf_link's to have the same net effect as just doing the last one (no effect on ld, which only ever does one ctf_link) rather than having the links be a sort of half-incremental not-really-intended mess. libctf/ChangeLog: PR libctf/29242 * ctf-impl.h (struct ctf_dict) [ctf_link_in_out]: New. * ctf-dedup.c (ctf_dedup_emit_type): Set it. * ctf-link.c (ctf_link_add_ctf_internal): Set the input CU name uniquely when clashes are found. (ctf_link_add): Document what repeated additions do. (ctf_new_per_cu_name): New, come up with a consistent name for a new per-CU dict. (ctf_link_deduplicating): Use it. (ctf_create_per_cu): Use it, and ctf_link_in_out, and set ctf_link_in_out properly. Don't overwrite per-CU dicts with per-CU dicts relating to different inputs. (ctf_link_add_cu_mapping): Prevent per-CU mappings being set up if we already have per-CU outputs. (ctf_link_one_variable): Adjust ctf_link_per_cu call. (ctf_link_deduplicating_one_symtypetab): Likewise. (ctf_link_empty_outputs): New, delete all the ctf_link_outputs and blank out ctf_link_in_out on the corresponding inputs. (ctf_link): Clarify the effect of multiple ctf_link calls. Empty ctf_link_outputs if it already exists rather than having the old output leak into the new link. Fix a variable name. * testsuite/config/default.exp (AR): Add. (OBJDUMP): Likewise. * testsuite/libctf-regression/libctf-repeat-cu.exp: New test. * testsuite/libctf-regression/libctf-repeat-cu*: Main program, library, and expected results for the test.
2022-04-28libctf: impose an ordering on conflicting typesNick Alcock1-1/+20
When two types conflict and they are not types which can have forwards (say, two arrays of different sizes with the same name in two different TUs) the CTF deduplicator uses a popularity contest to decide what to do: the type cited by the most other types ends up put into the shared dict, while the others are relegated to per-CU child dicts. This works well as long as one type *is* most popular -- but what if there is a tie? If several types have the same popularity count, we end up picking the first we run across and promoting it, and unfortunately since we are working over a dynhash in essentially arbitrary order, this means we promote a random one. So multiple runs of ld with the same inputs can produce different outputs! All the outputs are valid, but this is still undesirable. Adjust things to use the same strategy used to sort types on the output: when there is a tie, always put the type that appears in a CU that appeared earlier on the link line (and if there is somehow still a tie, which should be impossible, pick the type with the lowest type ID). Add a testcase -- and since this emerged when trying out extern arrays, check that those work as well (this requires a newer GCC, but since all GCCs that can emit CTF at all are unreleased this is probably OK as well). Fix up one testcase that has slight type ordering changes as a result of this change. libctf/ChangeLog: * ctf-dedup.c (ctf_dedup_detect_name_ambiguity): Use cd_output_first_gid to break ties. ld/ChangeLog: * testsuite/ld-ctf/array-conflicted-ordering.d: New test, using... * testsuite/ld-ctf/array-char-conflicting-1.c: ... this... * testsuite/ld-ctf/array-char-conflicting-2.c: ... and this. * testsuite/ld-ctf/array-extern.d: New test, using... * testsuite/ld-ctf/array-extern.c: ... this. * testsuite/ld-ctf/conflicting-typedefs.d: Adjust for ordering changes.
2022-03-25libtool.m4: fix the NM="/nm/over/here -B/option/with/path" caseNick Alcock1-7/+13
My previous nm patch handled all cases but one -- if the user set NM in the environment to a path which contained an option, libtool's nm detection tries to run nm against a copy of nm with the options in it: e.g. if NM was set to "nm --blargle", and nm was found in /usr/bin, the test would try to run "/usr/bin/nm --blargle /usr/bin/nm --blargle". This is unlikely to be desirable: in this case we should run "/usr/bin/nm --blargle /usr/bin/nm". Furthermore, as part of this nm has to detect when the passed-in $NM contains a path, and in that case avoid doing a path search itself. This too was thrown off if an option contained something that looked like a path, e.g. NM="nm -B../prev-gcc"; libtool then tries to run "nm -B../prev-gcc nm" which rarely works well (and indeed it looks to see whether that nm exists, finds it doesn't, and wrongly concludes that nm -p or whatever does not work). Fix all of these by clipping all options (defined as everything including and after the first " -") before deciding whether nm contains a path (but not using the clipped value for anything else), and then removing all options from the path-modified nm before looking to see whether that nm existed. NM=my-nm now does a path search and runs e.g. /usr/bin/my-nm -B /usr/bin/my-nm NM=/usr/bin/my-nm now avoids a path search and runs e.g. /usr/bin/my-nm -B /usr/bin/my-nm NM="my-nm -p../wombat" now does a path search and runs e.g. /usr/bin/my-nm -p../wombat -B /usr/bin/my-nm NM="../prev-binutils/new-nm -B../prev-gcc" now avoids a path search: ../prev-binutils/my-nm -B../prev-gcc -B ../prev-binutils/my-nm This seems to be all combinations, including those used by GCC bootstrap (which, before this commit, fails to bootstrap when configured --with-build-config=bootstrap-lto, because the lto plugin is now using --export-symbols-regex, which requires libtool to find a working nm, while also using -B../prev-gcc to point at the lto plugin associated with the GCC just built.) Regenerate all affected configure scripts. * libtool.m4 (LT_PATH_NM): Handle user-specified NM with options, including options containing paths.
2022-03-23libctf: add LIBCTF_WRITE_FOREIGN_ENDIAN debugging optionNick Alcock3-111/+144
libctf has always handled endianness differences by detecting foreign-endian CTF dicts on the input and endian-flipping them: dicts are always written in native endianness. This makes endian-awareness very low overhead, but it means that the foreign-endian code paths almost never get routinely tested, since "make check" usually reads in dicts ld has just written out: only a few corrupted-CTF tests are actually in fixed endianness, and even they only test the foreign- endian code paths when you run make check on a big-endian machine. (And the fix is surely not to add more .s-based tests like that, because they are a nightmare to maintain compared to the C-code-based ones.) To improve on this, add a new environment variable, LIBCTF_WRITE_FOREIGN_ENDIAN, which causes libctf to unconditionally endian-flip at ctf_write time, so the output is always in the wrong endianness. This then tests the foreign-endian read paths properly at open time. Make this easier by restructuring the writeout code in ctf-serialize.c, which duplicates the maybe-gzip-and-write-out code three times (once for ctf_write_mem, with thresholding, and once each for ctf_compress_write and ctf_write just so those can avoid thresholding and/or compression). Instead, have the latter two call the former with thresholds of 0 or (size_t) -1, respectively. The endian-flipping code itself gains a bit of complexity, because one single endian-flipper (flip_types) was assuming the input to be in foreign-endian form and assuming it could pull things out of the input once they had been flipped and make sense of them. At the cost of a few lines of duplicated initializations, teach it to read before flipping if we're flipping to foreign-endianness instead of away from it. libctf/ * ctf-impl.h (ctf_flip_header): No longer static. (ctf_flip): Likewise. * ctf-open.c (flip_header): Rename to... (ctf_flip_header): ... this, now it is not private to one file. (flip_ctf): Rename... (ctf_flip): ... this too. Add FOREIGN_ENDIAN arg. (flip_types): Likewise. Use it. (ctf_bufopen_internal): Adjust calls. * ctf-serialize.c (ctf_write_mem): Add flip_endian path via a newly-allocated bounce buffer. (ctf_compress_write): Move below ctf_write_mem and reimplement in terms of it. (ctf_write): Likewise. (ctf_gzwrite): Note that this obscure writeout function does not support endian-flipping.
2022-03-23libctf, ld: diagnose corrupted CTF header cth_strlenNick Alcock1-16/+29
The last section in a CTF dict is the string table, at an offset represented by the cth_stroff header field. Its length is recorded in the next field, cth_strlen, and the two added together are taken as the size of the CTF dict. Upon opening a dict, we check that none of the header offsets exceed this size, and we check when uncompressing a compressed dict that the result of the uncompression is the same length: but CTF dicts need not be compressed, and short ones are not. Uncompressed dicts just use the ctf_size without checking it. This field is thankfully almost unused: it is mostly used when reserializing a dict, which can't be done to dicts read off disk since they're read-only. However, when opening an uncompressed foreign-endian dict we have to copy it out of the mmaped region it is stored in so we can endian- swap it, and we use ctf_size when doing that. When the cth_strlen is corrupt, this can overrun. Fix this by checking the ctf_size in all uncompressed cases, just as we already do in the compressed case. Add a new test. This came to light because various corrupted-CTF raw-asm tests had an incorrect cth_strlen: fix all of them so they produce the expected error again. libctf/ PR libctf/28933 * ctf-open.c (ctf_bufopen_internal): Always check uncompressed CTF dict sizes against the section size in case the cth_strlen is corrupt. ld/ PR libctf/28933 * testsuite/ld-ctf/diag-strlen-invalid.*: New test, derived from diag-cttname-invalid.s. * testsuite/ld-ctf/diag-cttname-invalid.s: Fix incorrect cth_strlen. * testsuite/ld-ctf/diag-cttname-null.s: Likewise. * testsuite/ld-ctf/diag-cuname.s: Likewise. * testsuite/ld-ctf/diag-parlabel.s: Likewise. * testsuite/ld-ctf/diag-parname.s: Likewise.
2022-03-23include, libctf, ld: extend variable section to contain functions tooNick Alcock3-12/+57
The CTF variable section is an optional (usually-not-present) section in the CTF dict which contains name -> type mappings corresponding to data symbols that are present in the linker input but not in the output symbol table: the idea is that programs that use their own symbol- resolution mechanisms can use this section to look up the types of symbols they have found using their own mechanism. Because these removed symbols (mostly static variables, functions, etc) all have names that are unlikely to appear in the ELF symtab and because very few programs have their own symbol-resolution mechanisms, a special linker flag (--ctf-variables) is needed to emit this section. Historically, we emitted only removed data symbols into the variable section. This seemed to make sense at the time, but in hindsight it really doesn't: functions are symbols too, and a C program can look them up just like any other type. So extend the variable section so that it contains all static function symbols too (if it is emitted at all), with types of kind CTF_K_FUNCTION. This is a little fiddly. We relied on compiler assistance for data symbols: the compiler simply emits all data symbols twice, once into the symtypetab as an indexed symbol and once into the variable section. Rather than wait for a suitably adjusted compiler that does the same for function symbols, we can pluck unreported function symbols out of the symtab and add them to the variable section ourselves. While we're at it, we do the same with data symbols: this is redundant right now because the compiler does it, but it costs very little time and lets the compiler drop this kludge and save a little space in .o files. include/ * ctf.h: Mention the new things we can see in the variable section. ld/ * testsuite/ld-ctf/data-func-conflicted-vars.d: New test. libctf/ * ctf-link.c (ctf_link_deduplicating_variables): Duplicate symbols into the variable section too. * ctf-serialize.c (symtypetab_delete_nonstatic_vars): Rename to... (symtypetab_delete_nonstatics): ... this. Check the funchash when pruning redundant variables. (ctf_symtypetab_sect_sizes): Adjust accordingly. * NEWS: Describe this change.
2022-02-11libctf: delete unused libctf_TEXINFOSMike Frysinger2-2/+0
It's not clear what this was meant for, but it's not used by anything, and the info pages still generate fine without it.
2022-01-22Add markers for 2.38 branchNick Clifton1-0/+4
2022-01-02Update year range in copyright notice of binutils filesAlan Modra39-40/+40
The result of running etc/update-copyright.py --this-year, fixing all the files whose mode is changed by the script, plus a build with --enable-maintainer-mode --enable-cgen-maint=yes, then checking out */po/*.pot which we don't update frequently. The copy of cgen was with commit d1dd5fcc38ead reverted as that commit breaks building of bfp opcodes files.
2021-12-02libctf: workaround automake bug with conditional info pagesMike Frysinger3-20/+32
It looks like automake makes assumptions about its ability to build info pages based on the GNU standard behavior of shipping info pages with the distributions. So even though the info pages were conditionalized, and automake disabled some of the targets, it was still creeping in by way of unconditional INFO_DEPS settings. We can workaround this by adding a stub target for the info page when building info pages are disabled. This tricks automake into disabling its own extended generation target. I'll follow up with the automake folks to see what they think.
2021-12-02libctf: re-generate configureSimon Marchi1-2/+1
When configuring libctf, I get: config.status: error: cannot find input file: `doc/Makefile.in' This is because configure is out-of-date, re-generate it. Change-Id: Ie69acd33012211a4620661582c7d24ad6d2cd169
2021-12-01libctf: merge doc subdir up a levelMike Frysinger5-1014/+410
This avoids a recursive make into the doc subdir and speeds up the build slightly. It also allows for more parallelism.
2021-11-29libctf: enable silent build rulesMike Frysinger3-3/+43
Also add $(AM_V_xxx) to various manual rules in here.
2021-11-09doc/ctf-spec.texi: Remove "@validatemenus off"H.J. Lu1-1/+0
Remove @validatemenus from ctf-spec.texi, which has been removed from texinfo by commit a16dd1a9ece08568a1980b9a65a3a9090717997f Author: Gavin Smith <gavinsmith0123@gmail.com> Date: Mon Oct 12 16:32:37 2020 +0100 * doc/texinfo.texi (Writing a Menu, Customization Variables for @-Commands) (Command List), * doc/refcard/txirefcard.tex Remove @validatemenus. * tp/Texinfo/XS/Makefile.am (command_ids.h): Use gawk instead of awk. Avoid discouraged "$p" usage, using "$(p)" instead. * tp/Texinfo/XS/configure.ac: Check for gawk. commit 128acab3889b51809dc3bd3c6c74b61d13f7f5f4 Author: Gavin Smith <gavinsmith0123@gmail.com> Date: Thu Jan 3 14:51:53 2019 +0000 Update refcard. * doc/refcard/txirefcard.tex: @setfilename is no longer mandatory. Do not mention @validatemenus or explicitly giving @node pointers, as these are not very important features. PR libctf/28567 * doc/ctf-spec.texi: Remove "@validatemenus off".
2021-11-08libctf: add CTF format specificationNick Alcock8-40/+2857
It's been a long time since most of this was written: it's long past time to put it in the binutils source tree. It's believed correct and complete insofar as it goes: it documents format v3 (the current version) but not the libctf API or any earlier versions. (The earlier versions can be read by libctf but not generated by it, and you are highly unlikely ever to see an example of any of them.) libctf/ChangeLog 2021-11-08 Nick Alcock <nick.alcock@oracle.com> * doc/ctf-spec.texi: New file. * configure.ac (MAKEINFO): Add. (BUILD_INFO): Likewise. (AC_CONFIG_FILES) [doc/Makefile]: Add. * Makefile.am [BUILD_INFO] (SUBDIRS): Add doc/. * doc/Makefile.am: New file. * doc/Makefile.in: Likewise. * configure: Regenerated. * Makefile.in: Likewise.
2021-10-25libctf, ld: handle nonrepresentable types betterNick Alcock2-6/+17
ctf_type_visit (used, among other things, by the type dumping code) was aborting when it saw a nonrepresentable type anywhere: even a single structure member with a nonrepresentable type caused an abort with ECTF_NONREPRESENTABLE. This is not useful behaviour, given that the abort comes from a type-resolution we are only doing in order to determine whether the type is a structure or union. We know nonrepresentable types can't be either, so handle that case and pass the nonrepresentable type down. (The added test verifies that the dumper now handles this case and prints nonrepresentable structure members as it already does nonrepresentable top-level types, rather than skipping the whole structure -- or, without the previous commit, skipping the whole types section.) ld/ChangeLog 2021-10-25 Nick Alcock <nick.alcock@oracle.com> * testsuite/ld-ctf/nonrepresentable-member.*: New test. libctf/ChangeLog 2021-10-25 Nick Alcock <nick.alcock@oracle.com> * ctf-types.c (ctf_type_rvisit): Handle nonrepresentable types.
2021-10-25libctf: dump: do not stop dumping types on errorNick Alcock2-4/+14
If dumping of a single type fails, we obviously can't dump it; but just as obviously this doesn't make the other types in the types section invalid or undumpable. So we should not propagate errors seen when type-dumping, but rather ignore them and carry on, so we dump as many types as we can (leaving out the ones we can't grok). libctf/ChangeLog 2021-10-25 Nick Alcock <nick.alcock@oracle.com> * ctf-dump.c (ctf_dump_type): Do not abort on error.
2021-09-27libctf, lookup: fix bounds of pptrtab lookupNick Alcock4-2/+78
An off-by-one bug in the check for pptrtab lookup meant that we could access the pptrtab past its bounds (*well* past its bounds), particularly if we called ctf_lookup_by_name in a child dict with "*foo" where "foo" is a type that exists in the parent but not the child and no previous lookups by name have been carried out. (Note that "*foo" is not even a valid thing to call ctf_lookup_by_name with: foo * is. Nonetheless, users sometimes do call ctf_lookup_by_name with invalid content, and it should return ECTF_NOTYPE, not crash.) ctf_pptrtab_len, as its name suggests (and as other tests of it in ctf-lookup.c confirm), is one higher than the maximum valid permissible index, so the comparison is wrong. (Test added, which should fail pretty reliably in the presence of this bug on any machine with 4KiB pages.) libctf/ChangeLog 2021-09-27 Nick Alcock <nick.alcock@oracle.com> * ctf-lookup.c (ctf_lookup_by_name_internal): Fix pptrtab bounds. * testsuite/libctf-writable/pptrtab-writable-page-deep-lookup.*: New test.
2021-09-27libctf, testsuite: fix various warnings in testsNick Alcock11-18/+28
These warnings are all off by default, but if they do fire you get spurious ERRORs when running make check-libctf. libctf/ChangeLog 2021-09-27 Nick Alcock <nick.alcock@oracle.com> * testsuite/libctf-lookup/enum-symbol.c: Remove unused label. * testsuite/libctf-lookup/conflicting-type-syms.c: Remove unused variables. * testsuite/libctf-regression/pptrtab.c: Likewise. * testsuite/libctf-regression/type-add-unnamed-struct.c: Likewise. * testsuite/libctf-writable/pptrtab.c: Likewise. * testsuite/libctf-writable/reserialize-strtab-corruption.c: Likewise. * testsuite/libctf-regression/nonstatic-var-section-ld-r.c: Fix format string. * testsuite/libctf-regression/nonstatic-var-section-ld.c: Likewise. * testsuite/libctf-regression/nonstatic-var-section-ld.lk: Adjust. * testsuite/libctf-writable/symtypetab-nonlinker-writeout.c: Fix initializer.
2021-09-27libctf: fix handling of CTF symtypetab sections emitted by older GCCNick Alcock2-3/+11
Older (pre-upstreaming) GCC emits a function symtypetab section of a format never read by any extant libctf. We can detect such CTF dicts by the lack of the CTF_F_NEWFUNCINFO flag in their header, and we do so when reading in the symtypetab section -- but if the set of symbols with types is sufficiently sparse, even an older GCC will emit a function index section. In NEWFUNCINFO-capable compilers, this section will always be the exact same length as the corresponding function section (each is an array of uint32_t, associated 1:1 with each other). But this is not true for the older compiler, for which the sections are different lengths. We check to see if the function symtypetab section and its index are the same length, but we fail to skip this check when this is not a NEWFUNCINFO dict, and emit a spurious corruption error for a CTF dict we could have perfectly well opened and used. Fix trivial: check the flag (and fix the terrible grammar of the error message at the same time). libctf/ChangeLog 2021-09-27 Nick Alcock <nick.alcock@oracle.com> * ctf-open.c (ctf_bufopen_internal): Don't complain about corrupt function index symtypetab sections if this is an old-format function symtypetab section (which should be ignored in any case). Fix bad grammar.
2021-09-27configure: regenerate in all projects that use libtool.m4Nick Alcock3-50/+118
(including sim/, which has no changelog.) bfd/ChangeLog 2021-09-27 Nick Alcock <nick.alcock@oracle.com> * configure: Regenerate. binutils/ChangeLog 2021-09-27 Nick Alcock <nick.alcock@oracle.com> * configure: Regenerate. gas/ChangeLog 2021-09-27 Nick Alcock <nick.alcock@oracle.com> * configure: Regenerate. gprof/ChangeLog 2021-09-27 Nick Alcock <nick.alcock@oracle.com> * configure: Regenerate. ld/ChangeLog 2021-09-27 Nick Alcock <nick.alcock@oracle.com> * configure: Regenerate. libctf/ChangeLog 2021-09-27 Nick Alcock <nick.alcock@oracle.com> * configure: Regenerate. * Makefile.in: Regenerate. opcodes/ChangeLog 2021-09-27 Nick Alcock <nick.alcock@oracle.com> * configure: Regenerate. zlib/ChangeLog 2021-09-27 Nick Alcock <nick.alcock@oracle.com> * configure: Regenerate.
2021-09-27libctf: try several possibilities for linker versioning flagsNick Alcock4-11/+62
Checking for linker versioning by just grepping ld --help output for mentions of --version-script is inadequate now that Solaris 11.4 implements a --version-script with different semantics. Try linking a test program with a small wildcard-using version script with each supported set of flags in turn, to make sure that linker versioning is not only advertised but actually works. The Solaris "GNU-compatible" linker versioning is not quite GNU-compatible enough, but we can work around the differences by generating a new version script that removes the comments from the original (Solaris ld requires #-style comments), and making another version script for libctf-nonbfd in particular which doesn't mention any of the symbols that appear in libctf.la, to avoid Solaris ld introducing corresponding new NOTYPE symbols to match the version script. libctf/ChangeLog 2021-09-27 Nick Alcock <nick.alcock@oracle.com> PR libctf/27967 * configure.ac (VERSION_FLAGS): Replace with... (ac_cv_libctf_version_script): ... this multiple test. (VERSION_FLAGS_NOBFD): Substitute this too. * Makefile.am (libctf_nobfd_la_LDFLAGS): Use it. Split out... (libctf_ldflags_nover): ... non-versioning flags here. (libctf_la_LDFLAGS): Use it. * libctf.ver: Give every symbol not in libctf-nobfd a comment on the same line noting as much.
2021-09-27libctf: link against libiberty before linking in libbfd or libctf-nobfdNick Alcock3-2/+18
This ensures that the CTF_LIBADD, which always contains at least this when doing a shared link: -L`pwd`/../libiberty/pic -liberty appears in the link line before any requirements pulled in by libbfd.la, which include -liberty but because it is install-time do not include the -L`pwd`/../libiberty/pic portion (in an indirect dep like this, the path comes from the libbfd.la file, and is an install path). libiberty also appears after libbfd in the link line by virtue of libctf-nobfd.la, because libctf-nobfd has to follow libbfd in the link line, and that needs symbols from libiberty too. Without this, an installed liberty might well be pulled in by libbfd, and if --enable-install-libiberty is not specified this libiberty might be completely incompatible with what is being installed and break either or boht of libbfd and libctf. (The specific problem observed here is that bsearch_r was not present, but other problems might easily be observed in future too.) Because ld links against libctf, this has a tendency to break the system linker at install time too, if installing with --prefix=/usr. That's quite unpleasant to recover from. libctf/ChangeLog 2021-09-27 Nick Alcock <nick.alcock@oracle.com> PR libctf/27360 * Makefile.am (libctf_la_LIBADD): Link against libiberty before pulling in libbfd.la or pulling in libctf-nobfd.la. * Makefile.in: Regenerate.
2021-09-03CC_FOR_TARGET et alAlan Modra4-15/+17
The top level Makefile, the ld Makefile and others, define CC_FOR_TARGET to be a compiler for the binutils target machine. This is the compiler that should be used for almost all tests with C source. There are _FOR_TARGET versions of CFLAGS, CXX, and CXXFLAGS too. This was all supposed to work with the testsuite .exp files using CC for the target compiler, and CC_FOR_HOST for the host compiler, with the makefiles passing CC=$CC_FOR_TARGET and CC_FOR_HOST=$CC to the runtest invocation. One exception to the rule of using CC_FOR_TARGET is the native-only ld bootstrap test, which uses the newly built ld to link a copy of itself. Since the files being linked were created with the host compiler, the boostrap test should use CC and CFLAGS, in case some host compiler option provides needed libraries automatically. However, bootstrap.exp used CC where it should have used CC_FOR_HOST. I set about fixing that problem, then decided that playing games in the makefiles with CC was a bad idea. Not only is it confusing, but other dejagnu code knows about CC_FOR_TARGET. See dejagnu/target.exp. So this patch gets rid of the makefile variable renaming and changes all the .exp files to use the correct _FOR_TARGET variables. CC_FOR_HOST and CFLAGS_FOR_HOST disappear. A followup patch will correct bootstrap.exp to use CFLAGS, and a number of other things I noticed. binutils/ * testsuite/lib/binutils-common.exp (run_dump_test): Use CC_FOR_TARGET and CFLAGS_FOR_TARGET rather than CC and CFLAGS. ld/ * Makefile.am (check-DEJAGNU): Don't set CC to CC_FOR_TARGET and similar. Pass variables with unchanged names. Don't set CC_FOR_HOST or CFLAGS_FOR_HOST. * Makefile.in: Regenerate. * testsuite/config/default.exp: Update default CC and similar. (compiler_supports, plug_opt): Use CC_FOR_TARGET. * testsuite/ld-cdtest/cdtest.exp: Replace all uses of CC with CC_FOR_TARGET, and similarly for CFLAGS, CXX and CXXFLAGS. * testsuite/ld-auto-import/auto-import.exp: Likewise. * testsuite/ld-cygwin/exe-export.exp: Likewise. * testsuite/ld-elf/dwarf.exp: Likewise. * testsuite/ld-elf/indirect.exp: Likewise. * testsuite/ld-elf/shared.exp: Likewise. * testsuite/ld-elfcomm/elfcomm.exp: Likewise. * testsuite/ld-elfvers/vers.exp: Likewise. * testsuite/ld-elfvsb/elfvsb.exp: Likewise. * testsuite/ld-elfweak/elfweak.exp: Likewise. * testsuite/ld-gc/gc.exp: Likewise. * testsuite/ld-ifunc/ifunc.exp: Likewise. * testsuite/ld-mn10300/mn10300.exp: Likewise. * testsuite/ld-pe/pe-compile.exp: Likewise. * testsuite/ld-pe/pe-run.exp: Likewise. * testsuite/ld-pe/pe-run2.exp: Likewise. * testsuite/ld-pie/pie.exp: Likewise. * testsuite/ld-plugin/lto.exp: Likewise. * testsuite/ld-plugin/plugin.exp: Likewise. * testsuite/ld-scripts/crossref.exp: Likewise. * testsuite/ld-selective/selective.exp: Likewise. * testsuite/ld-sh/sh.exp: Likewise. * testsuite/ld-shared/shared.exp: Likewise. * testsuite/ld-srec/srec.exp: Likewise. * testsuite/ld-undefined/undefined.exp: Likewise. * testsuite/ld-unique/unique.exp: Likewise. * testsuite/ld-x86-64/tls.exp: Likewise. * testsuite/lib/ld-lib.exp: Likewise. libctf/ * Makefile.am (check-DEJAGNU): Don't set CC to CC_FOR_TARGET. Pass CC and CC_FOR_TARGET. Don't set CC_FOR_HOST. * Makefile.in: Regenerate. * testsuite/config/default.exp: Update default CC and similar. * testsuite/lib/ctf-lib.exp (run_native_host_cmd): Use CC rather than CC_FOR_HOST. (run_lookup_test): Use CC_FOR_TARGET and CFLAGS_FOR_TARGET.
2021-09-03ubsan: libctf: applying zero offset to null pointerAlan Modra1-1/+1
* ctf-open.c (init_symtab): Avoid ubsan error.
2021-09-03haiku tidyAlan Modra1-1/+1
--enable-maintainer-mode showed a number of files needing to be regenerated, and in the case of ld/Makefile.in that the file was regenerated by hand. Nothing to see here really. ld/ * Makefile.am (ALL_64_EMULATION_SOURCES): Sort haiku entry. * Makefile.in: Regenerate. * po/BLD-POTFILES.in: Regenerate. libctf/ * configure: Regenerate. zlib/ * configure: Regenerate.
2021-07-03Add markers for 2.37 branchNick Clifton1-0/+4
2021-05-09Use htab_eq_string in libctfAlan Modra4-18/+16
* ctf-impl.h (ctf_dynset_eq_string): Don't declare. * ctf-hash.c (ctf_dynset_eq_string): Delete function. * ctf-dedup.c (make_set_element): Use htab_eq_string. (ctf_dedup_atoms_init, ADD_CITER, ctf_dedup_init): Likewise. (ctf_dedup_conflictify_unshared): Likewise. (ctf_dedup_walk_output_mapping): Likewise.
2021-05-06libctf, ld: fix test results for upstream GCCNick Alcock3-3/+8
The tests currently in binutils are aimed at the original GCC-based implementation of CTF, which emitted CTF directly from GCC's internal representation. The approach now under review emits CTF from DWARF, with an eye to eventually doing this for all non-DWARF debuginfo-like formats GCC supports. It also uses a different flag to enable CTF emission (-gctf rather than -gt). Adjust the testsuite accordingly. Given that the ld testsuite results are dependent on type ordering, which we do not guarantee at all, it's amazing how little changes. We see a few type ordering differences, slices change because the old GCC was buggy (slices were emitted "backwards", from the wrong end of the machine word) and its expected results were wrong, and GCC now emits the underlying integral type for enumerated types, though CTF has no way to record this yet (coming in v4). GCC also now emits even hidden symbols into the symtab (and thus symtypetab), so one symtypetab test changes its expected results slightly to compensate. Also add tests for the CTF_K_UNKNOWN nonrepresentable type: this couldn't be done before now since the only GCC that emits CTF_K_UNKNOWN for nonrepresentable types is the new one. ld/ChangeLog 2021-05-06 Nick Alcock <nick.alcock@oracle.com> * testsuite/ld-ctf/ctf.exp: Use -gctf, not -gt. * testsuite/lib/ld-lib.exp: Likewise. * testsuite/ld-ctf/nonrepresentable-1.c: New test for nonrepresentable types. * testsuite/ld-ctf/nonrepresentable-2.c: Likewise. * testsuite/ld-ctf/nonrepresentable.d: Likewise. * testsuite/ld-ctf/array.d: Larger type section. * testsuite/ld-ctf/data-func-conflicted.d: Likewise. * testsuite/ld-ctf/enums.d: Likewise. * testsuite/ld-ctf/conflicting-enums.d: Don't compare types. * testsuite/ld-ctf/cross-tu-cyclic-conflicting.d: Changed type order. * testsuite/ld-ctf/cross-tu-noncyclic.d: Likewise. * testsuite/ld-ctf/slice.d: Adjust for improved slice emission. libctf/ChangeLog 2021-05-06 Nick Alcock <nick.alcock@oracle.com> * testsuite/lib/ctf-lib.exp: Use -gctf, not -gt. * testsuite/libctf-regression/nonstatic-var-section-ld-r.lk: Hidden symbols now get into the symtypetab anyway.
2021-05-06libctf, include: support an alternative encoding for nonrepresentable typesNick Alcock7-10/+69
Before now, types that could not be encoded in CTF were represented as references to type ID 0, which does not itself appear in the dictionary. This choice is annoying in several ways, principally that it forces generators and consumers of CTF to grow special cases for types that are referenced in valid dicts but don't appear. Allow an alternative representation (which will become the only representation in format v4) whereby nonrepresentable types are encoded as actual types with kind CTF_K_UNKNOWN (an already-existing kind theoretically but not in practice used for padding, with value 0). This is backward-compatible, because CTF_K_UNKNOWN was not used anywhere before now: it was used in old-format function symtypetabs, but these were never emitted by any compiler and the code to handle them in libctf likely never worked and was removed last year, in favour of new-format symtypetabs that contain only type IDs, not type kinds. In order to link this type, we need an API addition to let us add types of unknown kind to the dict: we let them optionally have names so that GCC can emit many different unknown types and those types with identical names will be deduplicated together. There are also small tweaks to the deduplicator to actually dedup such types, to let opening of dicts with unknown types with names work, to return the ECTF_NONREPRESENTABLE error on resolution of such types (like ID 0), and to print their names as something useful but not a valid C identifier, mostly for the sake of the dumper. Tests added in the next commit. include/ChangeLog 2021-05-06 Nick Alcock <nick.alcock@oracle.com> * ctf.h (CTF_K_UNKNOWN): Document that it can be used for nonrepresentable types, not just padding. * ctf-api.h (ctf_add_unknown): New. libctf/ChangeLog 2021-05-06 Nick Alcock <nick.alcock@oracle.com> * ctf-open.c (init_types): Unknown types may have names. * ctf-types.c (ctf_type_resolve): CTF_K_UNKNOWN is as non-representable as type ID 0. (ctf_type_aname): Print unknown types. * ctf-dedup.c (ctf_dedup_hash_type): Do not early-exit for CTF_K_UNKNOWN types: they have real hash values now. (ctf_dedup_rwalk_one_output_mapping): Treat CTF_K_UNKNOWN types like other types with no referents: call the callback and do not skip them. (ctf_dedup_emit_type): Emit via... * ctf-create.c (ctf_add_unknown): ... this new function. * libctf.ver (LIBCTF_1.2): Add it.
2021-03-25libctf: fix ELF-in-BFD checks in the presence of ASANNick Alcock3-13/+18
The address sanitizer contains a redirector that captures dlopen calls, so checks for dlopen with AC_SEARCH_LIBS will always conclude that dlopen is present when the sanitizer is on. This means it won't add -ldl to LIBS even if needed, and the immediately-following attempt to actually link with -lbfd will fail because libbfd also needs dlsym, which ASAN does *not* contain a redirector for. If we check for dlsym instead of dlopen, the check works whether ASAN is on or off. (bfd uses both in close proximity: if it needs one, it will always need the other.) libctf/ChangeLog 2021-03-25 Nick Alcock <nick.alcock@oracle.com> * configure.ac: Check for dlsym, not dlopen. * configure: Regenerate.
2021-03-25libctf: fix memory leak in a testNick Alcock2-0/+6
Harmless, but causes noise that makes it harder to spot other leaks. libctf/ChangeLog 2021-03-25 Nick Alcock <nick.alcock@oracle.com> * testsuite/libctf-writable/symtypetab-nonlinker-writeout.c: Don't leak buf.
2021-03-25libctf: don't dereference out-of-bounds locations in the qualifier hashtabNick Alcock2-3/+13
isqualifier, which is used by ctf_lookup_by_name to figure out if a given word in a type name is a qualifier, takes the address of a possibly out-of-bounds location before checking its bounds. In any reasonable compiler this will just lead to a harmless address computation that is then discarded if out-of-bounds, but it's still undefined behaviour and the sanitizer rightly complains. libctf/ChangeLog 2021-03-25 Nick Alcock <nick.alcock@oracle.com> PR libctf/27628 * ctf-lookup.c (isqualifier): Don't dereference out-of-bounds qhash values.
2021-03-25libctf: make ctf_bfdopen_ctfsect a debugger entry pointNick Alcock2-0/+6
This makes it possible to use LIBCTF_DEBUG to debug things that happen before the ctf_bfdopen_internal call that ctf_bfdopen_ctfsect eventually thunks down to (symtab/strtab lookup, archive opening, etc). This is not important for ctf_open callers, since ctf_fdopen already calls libctf_init_debug, but ctf_bfdopen_ctfsect is a public entry point that can be called directly (e.g. objdump and readelf both do so). libctf/ChangeLog 2021-03-25 Nick Alcock <nick.alcock@oracle.com> * ctf-open-bfd.c (ctf_bfdopen_ctfsect): Initialize debugging.
2021-03-25libctf, serialize: functions with no args have a NULL dtd_vlenNick Alcock2-1/+9
Every place that accesses a function's dtd_vlen accesses it only if the number of args is nonzero, except the serializer, which always tries to memcpy it. The number of bytes it memcpys in this case is zero, but it is still undefined behaviour to copy zero bytes from a null pointer. So check for this case explicitly. libctf/ChangeLog 2021-03-25 Nick Alcock <nick.alcock@oracle.com> PR libctf/27628 * ctf-serialize.c (ctf_emit_type_sect): Allow for a NULL vlen in CTF_K_FUNCTION types.
2021-03-25libctf, dump: do not emit size or alignment if it would errorNick Alcock2-5/+12
When we dump normal types, we emit their size and/or alignment: but size and alignment dumping can return errors if the type is part of a chain that terminates in a forward. Emitting 0xffffffff as a size or alignment is unhelpful, so simply skip emitting this info for any type for which size or alignment checks return an error, no matter what the error is. libctf/ChangeLog 2021-03-25 Nick Alcock <nick.alcock@oracle.com> * ctf-dump.c (ctf_dump_format_type): Don't emit size or alignment on error.
2021-03-21Provide an inline startswith function in bfd.hAlan Modra2-0/+5
bfd/ * bfd-in.h (startswith): New inline. (CONST_STRNEQ): Use startswith. * bfd-in2.h: Regenerate. gdbsupport/ * common-utils.h (startswith): Delete version now supplied by bfd.h. libctf/ * ctf-impl.h: Include string.h.
2021-03-18libctf: support encodings for enumsNick Alcock3-2/+17
The previous commit started to error-check the lookup of ctf_type_encoding for the underlying type that is internally done when carrying out a ctf_type_encoding on a slice. Unfortunately, enums have no encoding, so this has historically been returning an error (which is ignored) and then populating the cte_format with uninitialized data. Now the error is not ignored, this is returning an error, which breaks linking of CTF containing bitfields of enumerated type. CTF format v3 does not record the actual underlying type of a enum, but we can mock up something that is not *too* wrong, and that is at any rate better than uninitialized data. ld/ChangeLog 2021-03-18 Nick Alcock <nick.alcock@oracle.com> * testsuite/ld-ctf/slice.c: Check slices of enums too. * testsuite/ld-ctf/slice.d: Results adjusted. libctf/ChangeLog 2021-03-18 Nick Alcock <nick.alcock@oracle.com> * ctf-types.c (ctf_type_encoding): Support, after a fashion, for enums. * ctf-dump.c (ctf_dump_format_type): Do not report enums' degenerate encoding.
2021-03-18libctf: a couple of small error-handling fixesNick Alcock3-10/+25
Out-of-memory errors initializing the string atoms table were disregarded (though they would have caused a segfault very shortly afterwards). Errors hashing types during deduplication were only reported if they happened on the output dict, which is almost never the case (most errors are going to be on the dict we're working over, which is going to be one of the inputs). (The error was detected in both cases, but the errno was extracted from the wrong dict.) libctf/ChangeLog 2021-03-18 Nick Alcock <nick.alcock@oracle.com> * ctf-dedup.c (ctf_dedup_rhash_type): Report errors on the input dict properly. * ctf-open.c (ctf_bufopen_internal): Report errors initializing the atoms table.
2021-03-18libctf: types: unify code dealing with small-vs-large struct membersNick Alcock3-157/+150
This completes the job of unifying what was once three separate code paths full of duplication for every function dealing with querying the properties of struct and union members. The dynamic code path was already removed: this change removes the distinction between small and large members, by adding a helper that copies out members from the vlen, expanding small members into large ones as it does so. This makes it possible to have *more* representations of things like structure members without needing to change the querying functions at all. It also lets us check for buffer overruns more effectively, verifying that we don't accidentally overrun the end of the vlen in either the dynamic or static type case. libctf/ChangeLog 2021-03-18 Nick Alcock <nick.alcock@oracle.com> * ctf-impl.h (ctf_next_t) <ctn_tp>: New. <u.ctn_mp>: Remove. <u.ctn_lmp>: Remove. <u.ctn_vlen>: New. * ctf-types.c (ctf_struct_member): New. (ctf_member_next): Use it, dropping separate large/small code paths. (ctf_type_align): Likewise. (ctf_member_info): Likewise. (ctf_type_rvisit): Likewise.
2021-03-18libctf: eliminate dtd_u, part 5: structs / unionsNick Alcock8-410/+323
Eliminate the dynamic member storage for structs and unions as we have for other dynamic types. This is much like the previous enum elimination, except that structs and unions are the only types for which a full-sized ctf_type_t might be needed. Up to now, this decision has been made in the individual ctf_add_{struct,union}_sized functions and duplicated in ctf_add_member_offset. The vlen machinery lets us simplify this, always allocating a ctf_lmember_t and setting the dtd_data's ctt_size to CTF_LSIZE_SENT: we figure out whether this is really justified and (almost always) repack things down into a ctf_stype_t at ctf_serialize time. This allows us to eliminate the dynamic member paths from the iterators and query functions in ctf-types.c in favour of always using the large-structure vlen stuff for dynamic types (the diff is ugly but that's just because of the volume of reindentation this calls for). This also means the large-structure vlen stuff gets more heavily tested, which is nice because it was an almost totally unused code path before now (it only kicked in for structures of size >4GiB, and how often do you see those?) The only extra complexity here is ctf_add_type. Back in the days of the nondeduplicating linker this was called a ridiculous number of times for countless identical copies of structures: eschewing the repeated lookups of the dtd in ctf_add_member_offset and adding the members directly saved an amazing amount of time. Now the nondeduplicating linker is gone, this is extreme overoptimization: we can rip out the direct addition and use ctf_member_next and ctf_add_member_offset, just like ctf_dedup_emit does. We augment a ctf_add_type test to try adding a self-referential struct, the only thing the ctf_add_type part of this change really perturbs. This completes the elimination of dtd_u. libctf/ChangeLog 2021-03-18 Nick Alcock <nick.alcock@oracle.com> * ctf-impl.h (ctf_dtdef_t) <dtu_members>: Remove. <dtd_u>: Likewise. (ctf_dmdef_t): Remove. (struct ctf_next) <u.ctn_dmd>: Remove. * ctf-create.c (INITIAL_VLEN): New, more-or-less arbitrary initial vlen size. (ctf_add_enum): Use it. (ctf_dtd_delete): Do not free the (removed) dmd; remove string refs from the vlen on struct deletion. (ctf_add_struct_sized): Populate the vlen: do it by hand if promoting forwards. Always populate the full-size lsizehi/lsizelo members. (ctf_add_union_sized): Likewise. (ctf_add_member_offset): Set up the vlen rather than the dmd. Expand it as needed, repointing string refs via ctf_str_move_pending. Add the member names as pending strings. Always populate the full-size lsizehi/lsizelo members. (membadd): Remove, folding back into... (ctf_add_type_internal): ... here, adding via an ordinary ctf_add_struct_sized and _next iteration rather than doing everything by hand. * ctf-serialize.c (ctf_copy_smembers): Remove this... (ctf_copy_lmembers): ... and this... (ctf_emit_type_sect): ... folding into here. Figure out if a ctf_stype_t is needed here, not in ctf_add_*_sized. (ctf_type_sect_size): Figure out the ctf_stype_t stuff the same way here. * ctf-types.c (ctf_member_next): Remove the dmd path and always use the vlen. Force large-structure usage for dynamic types. (ctf_type_align): Likewise. (ctf_member_info): Likewise. (ctf_type_rvisit): Likewise. * testsuite/libctf-regression/type-add-unnamed-struct-ctf.c: Add a self-referential type to this test. * testsuite/libctf-regression/type-add-unnamed-struct.c: Adjusted accordingly. * testsuite/libctf-regression/type-add-unnamed-struct.lk: Likewise.
2021-03-18libctf: eliminate dtd_u, part 4: enumsNick Alcock8-122/+277
This is the first tricky one, the first complex multi-entry vlen containing strings. To handle this in vlen form, we have to handle pending refs moving around on realloc. We grow vlen regions using a new ctf_grow_vlen function, and iterate through the existing enums every time a grow happens, telling the string machinery the distance between the old and new vlen region and letting it adjust the pending refs accordingly. (This avoids traversing all outstanding refs to find the refs that need adjusting, at the cost of having to traverse one enum: an obvious major performance win.) Addition of enums themselves (and also structs/unions later) is a bit trickier than earlier forms, because the type might be being promoted from a forward, and forwards have no vlen: so we have to spot that and create it if needed. Serialization of enums simplifies down to just telling the string machinery about the string refs; all the enum type-lookup code loses all its dynamic member lookup complexity entirely. A new test is added that iterates over (and gets values of) an enum with enough members to force a round of vlen growth. libctf/ChangeLog 2021-03-18 Nick Alcock <nick.alcock@oracle.com> * ctf-impl.h (ctf_dtdef_t) <dtd_vlen_alloc>: New. (ctf_str_move_pending): Declare. * ctf-string.c (ctf_str_add_ref_internal): Fix error return. (ctf_str_move_pending): New. * ctf-create.c (ctf_grow_vlen): New. (ctf_dtd_delete): Zero out the vlen_alloc after free. Free the vlen later: iterate over it and free enum name refs first. (ctf_add_generic): Populate dtd_vlen_alloc from vlen. (ctf_add_enum): populate the vlen; do it by hand if promoting forwards. (ctf_add_enumerator): Set up the vlen rather than the dmd. Expand it as needed, repointing string refs via ctf_str_move_pending. Add the enumerand names as pending strings. * ctf-serialize.c (ctf_copy_emembers): Remove. (ctf_emit_type_sect): Copy the vlen into place and ref the strings. * ctf-types.c (ctf_enum_next): The dynamic portion now uses the same code as the non-dynamic. (ctf_enum_name): Likewise. (ctf_enum_value): Likewise. * testsuite/libctf-lookup/enum-many-ctf.c: New test. * testsuite/libctf-lookup/enum-many.lk: New test.
2021-03-18libctf: do not corrupt strings across ctf_serializeNick Alcock8-12/+209
The preceding change revealed a new bug: the string table is sorted for better compression, so repeated serialization with type (or member) additions in the middle can move strings around. But every serialization flushes the set of refs (the memory locations that are automatically updated with a final string offset when the strtab is updated), so if we are not to have string offsets go stale, we must do all ref additions within the serialization code (which walks the complete set of types and symbols anyway). Unfortunately, we were adding one ref in another place: the type name in the dynamic type definitions, which has a ref added to it by ctf_add_generic. So adding a type, serializing (via, say, one of the ctf_write functions), adding another type with a name that sorts earlier, and serializing again will corrupt the name of the first type because it no longer had a ref pointing to its dtd entry's name when its string offset was shifted later in the strtab to mae way for the other type. To ensure that we don't miss strings, we also maintain a set of *pending refs* that will be added later (during serialization), and remove entries from that set when the ref is finally added. We always use ctf_str_add_pending outside ctf-serialize.c, ensure that ctf_serialize adds all strtab offsets as refs (even those in the dtds) on every serialization, and mandate that no refs are live on entry to ctf_serialize and that all pending refs are gone before strtab finalization. (Of necessity ctf_serialize has to traverse all strtab offsets in the dtds in order to serialize them, so adding them as refs at the same time is easy.) (Note that we still can't erase unused atoms when we roll back, though we can erase unused refs: members and enums are still not removed by rollbacks and might reference strings added after the snapshot.) libctf/ChangeLog 2021-03-18 Nick Alcock <nick.alcock@oracle.com> * ctf-hash.c (ctf_dynset_elements): New. * ctf-impl.h (ctf_dynset_elements): Declare it. (ctf_str_add_pending): Likewise. (ctf_dict_t) <ctf_str_pending_ref>: New, set of refs that must be added during serialization. * ctf-string.c (ctf_str_create_atoms): Initialize it. (CTF_STR_ADD_REF): New flag. (CTF_STR_MAKE_PROVISIONAL): Likewise. (CTF_STR_PENDING_REF): Likewise. (ctf_str_add_ref_internal): Take a flags word rather than int params. Populate, and clear out, ctf_str_pending_ref. (ctf_str_add): Adjust accordingly. (ctf_str_add_external): Likewise. (ctf_str_add_pending): New. (ctf_str_remove_ref): Also remove the potential ref if it is a pending ref. * ctf-serialize.c (ctf_serialize): Prohibit addition of strings with ctf_str_add_ref before serialization. Ensure that the ctf_str_pending_ref set is empty before strtab finalization. (ctf_emit_type_sect): Add a ref to the ctt_name. * ctf-create.c (ctf_add_generic): Add the ctt_name as a pending ref. * testsuite/libctf-writable/reserialize-strtab-corruption.*: New test.
2021-03-18libctf: don't lose track of all valid types upon serializationNick Alcock2-0/+6
One pattern which is rarely done in libctf but which is meant to work is this: ctf_create(); ctf_add_*(); // add stuff ctf_type_*() // look stuff up ctf_write_*(); ctf_add_*(); // should still work ctf_type_*() // so should this ctf_write_*(); // and this i.e., writing out a dict should not break it and you should be able to do everything you could do with it before, including writing it out again. Unfortunately this has been broken for a while because the field which indicates the maximum valid type ID was not preserved across serialization: so type additions after serialization would overwrite types (obviously disastrous) and type lookups would just fail. Fix trivial. libctf/ChangeLog 2021-03-18 Nick Alcock <nick.alcock@oracle.com> * ctf-serialize.c (ctf_serialize): Preserve ctf_typemax across serialization.