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| author | Sebastian Huber <sebastian.huber@embedded-brains.de> | 2017-10-18 07:36:38 +0000 |
|---|---|---|
| committer | Sebastian Huber <sh@gcc.gnu.org> | 2017-10-18 07:36:38 +0000 |
| commit | f381d87aa5928ecdfe531b2c8706843f65c951b9 (patch) | |
| tree | c904b831e08df4ea1a6bdb8641008a5f121d6e63 /gcc | |
| parent | 173a960ac907a353ac9de8bca9948ef9d41a7ec2 (diff) | |
| download | gcc-f381d87aa5928ecdfe531b2c8706843f65c951b9.zip gcc-f381d87aa5928ecdfe531b2c8706843f65c951b9.tar.gz gcc-f381d87aa5928ecdfe531b2c8706843f65c951b9.tar.bz2 | |
Update -ffunction/data-sections documentation
gcc/
* doc/invoke.texi (ffunction-sections and fdata-sections):
Update.
From-SVN: r253842
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/doc/invoke.texi | 32 |
2 files changed, 25 insertions, 12 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index c8a4680..a59161d 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2017-10-18 Sebastian Huber <sebastian.huber@embedded-brains.de> + + * doc/invoke.texi (ffunction-sections and fdata-sections): + Update. + 2017-10-17 Eric Botcazou <ebotcazou@adacore.com> * tree-ssa-loop-ivopts.c (add_autoinc_candidates): Bail out only if diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 6518ac0..5e88279 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -9712,18 +9712,26 @@ file if the target supports arbitrary sections. The name of the function or the name of the data item determines the section's name in the output file. -Use these options on systems where the linker can perform optimizations -to improve locality of reference in the instruction space. Most systems -using the ELF object format and SPARC processors running Solaris 2 have -linkers with such optimizations. AIX may have these optimizations in -the future. - -Only use these options when there are significant benefits from doing -so. When you specify these options, the assembler and linker -create larger object and executable files and are also slower. -You cannot use @command{gprof} on all systems if you -specify this option, and you may have problems with debugging if -you specify both this option and @option{-g}. +Use these options on systems where the linker can perform optimizations to +improve locality of reference in the instruction space. Most systems using the +ELF object format have linkers with such optimizations. On AIX, the linker +rearranges sections (CSECTs) based on the call graph. The performance impact +varies. + +Together with a linker garbage collection (linker @option{--gc-sections} +option) these options may lead to smaller statically-linked executables (after +stripping). + +On ELF/DWARF systems these options do not degenerate the quality of the debug +information. There could be issues with other object files/debug info formats. + +Only use these options when there are significant benefits from doing so. When +you specify these options, the assembler and linker create larger object and +executable files and are also slower. These options affect code generation. +They prevent optimizations by the compiler and assembler using relative +locations inside a translation unit since the locations are unknown until +link time. An example of such an optimization is relaxing calls to short call +instructions. @item -fbranch-target-load-optimize @opindex fbranch-target-load-optimize |