aboutsummaryrefslogtreecommitdiff
path: root/gas/doc
diff options
context:
space:
mode:
authorDave Korn <dave.korn@artimi.com>2009-05-19 16:08:08 +0000
committerDave Korn <dave.korn@artimi.com>2009-05-19 16:08:08 +0000
commitc1711530e652a14bc0df9b603c73e350b5dfe5ec (patch)
treef0e82c9c384277dc508547d786bbc912eac7edf8 /gas/doc
parentfbdebf465713844d23625ae09e0ae4995418328b (diff)
downloadgdb-c1711530e652a14bc0df9b603c73e350b5dfe5ec.zip
gdb-c1711530e652a14bc0df9b603c73e350b5dfe5ec.tar.gz
gdb-c1711530e652a14bc0df9b603c73e350b5dfe5ec.tar.bz2
==> bfd/ChangeLog <==
2009-05-19 Dave Korn <dave.korn.cygwin@gmail.com> * cofflink.c (process_embedded_commands): Ignore "-aligncomm". ==> gas/ChangeLog <== 2009-05-19 Dave Korn <dave.korn.cygwin@gmail.com> * NEWS: Mention new feature. * config/obj-coff.c (obj_coff_common_parse): New function. (obj_coff_comm): Likewise. (coff_pseudo_table): Override default ".comm" definition on PE. * doc/as.texinfo: Document new feature. ==> gas/testsuite/ChangeLog <== 2009-05-19 Dave Korn <dave.korn.cygwin@gmail.com> * gas/pe/: New directory for PE format-specific tests. * gas/pe/aligncomm-a.d: New test pattern file. * gas/pe/aligncomm-a.s: New test source file. * gas/pe/aligncomm-b.d: New test pattern file. * gas/pe/aligncomm-b.s: New test source file. * gas/pe/aligncomm-c.d: New test pattern file. * gas/pe/aligncomm-c.s: New test source file. * gas/pe/aligncomm-d.d: New test pattern file. * gas/pe/aligncomm-d.s: New test source file. * gas/pe/pe.exp: New test control script. * lib/gas-defs.exp (is_pecoff_format): New function. ==> ld/ChangeLog <== 2009-05-19 Dave Korn <dave.korn.cygwin@gmail.com> * NEWS: Mention new feature. * deffile.h (def_file_aligncomm): Add new struct definition. (def_file): Add new def_file_aligncomm member. * deffilep.y (%token): Add new ALIGNCOMM token. (command): Add production rule for ALIGNCOMM. (def_file_free): Free any chained def_file_aligncomm structs. (diropts[]): Add entry for '-aligncomm' .drectve command. (def_aligncomm): New grammar function. * ld.texinfo: Document new feature. * pe-dll.c (process_def_file): Rename from this ... (process_def_file_and_drectve): ... to this, updating all callers, and process any aligncomms chained to the def file after scanning all .drectve sections. (generate_edata): Updated to match. (pe_dll_build_sections): Likewise. ==> ld/testsuite/ChangeLog <== 2009-05-19 Dave Korn <dave.korn.cygwin@gmail.com> * ld-pe/aligncomm-1.c: New test source file. * ld-pe/aligncomm-2.c: Likewise. * ld-pe/aligncomm-3.c: Likewise. * ld-pe/aligncomm-4.c: Likewise. * ld-pe/aligncomm.d: New test pattern file. * ld-pe/direct.exp: Deleted, and content moved into ... * ld-pe/pe-run.exp: ... New common file for all PE run tests. * ld-pe/vers-script.exp: Deleted, and content merged into ... * ld-pe/pe-compile.exp: ... New common file for PE tests needing a compiler, adding aligned common tests. * ld-pe/pe.exp: Update header comment.
Diffstat (limited to 'gas/doc')
-rw-r--r--gas/doc/as.texinfo25
1 files changed, 16 insertions, 9 deletions
diff --git a/gas/doc/as.texinfo b/gas/doc/as.texinfo
index 9871fe2..e4f7984 100644
--- a/gas/doc/as.texinfo
+++ b/gas/doc/as.texinfo
@@ -4308,16 +4308,23 @@ absolute expression. If @code{@value{LD}} sees multiple common symbols with
the same name, and they do not all have the same size, it will allocate space
using the largest size.
-@ifset ELF
-When using ELF, the @code{.comm} directive takes an optional third argument.
-This is the desired alignment of the symbol, specified as a byte boundary (for
-example, an alignment of 16 means that the least significant 4 bits of the
-address should be zero). The alignment must be an absolute expression, and it
-must be a power of two. If @code{@value{LD}} allocates uninitialized memory
-for the common symbol, it will use the alignment when placing the symbol. If
-no alignment is specified, @command{@value{AS}} will set the alignment to the
+@ifset COFF-ELF
+When using ELF or (as a GNU extension) PE, the @code{.comm} directive takes
+an optional third argument. This is the desired alignment of the symbol,
+specified for ELF as a byte boundary (for example, an alignment of 16 means
+that the least significant 4 bits of the address should be zero), and for PE
+as a power of two (for example, an alignment of 5 means aligned to a 32-byte
+boundary). The alignment must be an absolute expression, and it must be a
+power of two. If @code{@value{LD}} allocates uninitialized memory for the
+common symbol, it will use the alignment when placing the symbol. If no
+alignment is specified, @command{@value{AS}} will set the alignment to the
largest power of two less than or equal to the size of the symbol, up to a
-maximum of 16.
+maximum of 16 on ELF, or the default section alignment of 4 on PE@footnote{This
+is not the same as the executable image file alignment controlled by @code{@value{LD}}'s
+@samp{--section-alignment} option; image file sections in PE are aligned to
+multiples of 4096, which is far too large an alignment for ordinary variables.
+It is rather the default alignment for (non-debug) sections within object
+(@samp{*.o}) files, which are less strictly aligned.}.
@end ifset
@ifset HPPA