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In assemly code, the section flag 'R' sets the SHF_GNU_RETAIN flag to indicate that the section must be preserved by the linker. Add SECTION_RETAIN to indicate a section should be retained by the linker and set SECTION_RETAIN on section for the preserved symbol if assembler supports SHF_GNU_RETAIN. All retained symbols are placed in separate sections with .section .data.rel.local.preserved_symbol,"awR" preserved_symbol: ... .section .data.rel.local,"aw" not_preserved_symbol: ... to avoid .section .data.rel.local,"awR" preserved_symbol: ... not_preserved_symbol: ... which places not_preserved_symbol definition in the SHF_GNU_RETAIN section. gcc/ 2020-12-01 H.J. Lu <hjl.tools@gmail.com> * configure.ac (HAVE_GAS_SHF_GNU_RETAIN): New. Define 1 if the assembler supports marking sections with SHF_GNU_RETAIN flag. * output.h (SECTION_RETAIN): New. Defined as 0x4000000. (SECTION_MACH_DEP): Changed from 0x4000000 to 0x8000000. (default_unique_section): Add a bool argument. * varasm.c (get_section): Set SECTION_RETAIN for the preserved symbol with HAVE_GAS_SHF_GNU_RETAIN. (resolve_unique_section): Used named section for the preserved symbol if assembler supports SHF_GNU_RETAIN. (get_variable_section): Handle the preserved common symbol with HAVE_GAS_SHF_GNU_RETAIN. (default_elf_asm_named_section): Require the full declaration and use the 'R' flag for SECTION_RETAIN. * config.in: Regenerated. * configure: Likewise. * doc/sourcebuild.texi: Document R_flag_in_section. gcc/testsuite/ 2020-12-01 H.J. Lu <hjl.tools@gmail.com> Jozef Lawrynowicz <jozef.l@mittosystems.com> * c-c++-common/attr-used.c: Check the 'R' flag. * c-c++-common/attr-used-2.c: Likewise. * c-c++-common/attr-used-3.c: New test. * c-c++-common/attr-used-4.c: Likewise. * gcc.c-torture/compile/attr-used-retain-1.c: Likewise. * gcc.c-torture/compile/attr-used-retain-2.c: Likewise. * lib/target-supports.exp (check_effective_target_R_flag_in_section): New proc. |
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| config | ||
| contrib | ||
| fixincludes | ||
| gcc | ||
| gnattools | ||
| gotools | ||
| include | ||
| INSTALL | ||
| intl | ||
| libada | ||
| libatomic | ||
| libbacktrace | ||
| libcc1 | ||
| libcpp | ||
| libdecnumber | ||
| libffi | ||
| libgcc | ||
| libgfortran | ||
| libgo | ||
| libgomp | ||
| libhsail-rt | ||
| libiberty | ||
| libitm | ||
| libobjc | ||
| liboffloadmic | ||
| libphobos | ||
| libquadmath | ||
| libsanitizer | ||
| libssp | ||
| libstdc++-v3 | ||
| libvtv | ||
| lto-plugin | ||
| maintainer-scripts | ||
| zlib | ||
| .dir-locals.el | ||
| .gitattributes | ||
| .gitignore | ||
| ABOUT-NLS | ||
| ar-lib | ||
| ChangeLog | ||
| ChangeLog.jit | ||
| ChangeLog.tree-ssa | ||
| compile | ||
| config-ml.in | ||
| config.guess | ||
| config.rpath | ||
| config.sub | ||
| configure | ||
| configure.ac | ||
| COPYING | ||
| COPYING3 | ||
| COPYING3.LIB | ||
| COPYING.LIB | ||
| COPYING.RUNTIME | ||
| depcomp | ||
| install-sh | ||
| libtool-ldflags | ||
| libtool.m4 | ||
| lt~obsolete.m4 | ||
| ltgcc.m4 | ||
| ltmain.sh | ||
| ltoptions.m4 | ||
| ltsugar.m4 | ||
| ltversion.m4 | ||
| MAINTAINERS | ||
| Makefile.def | ||
| Makefile.in | ||
| Makefile.tpl | ||
| missing | ||
| mkdep | ||
| mkinstalldirs | ||
| move-if-change | ||
| multilib.am | ||
| README | ||
| symlink-tree | ||
| test-driver | ||
| ylwrap | ||
This directory contains the GNU Compiler Collection (GCC). The GNU Compiler Collection is free software. See the files whose names start with COPYING for copying permission. The manuals, and some of the runtime libraries, are under different terms; see the individual source files for details. The directory INSTALL contains copies of the installation information as HTML and plain text. The source of this information is gcc/doc/install.texi. The installation information includes details of what is included in the GCC sources and what files GCC installs. See the file gcc/doc/gcc.texi (together with other files that it includes) for usage and porting information. An online readable version of the manual is in the files gcc/doc/gcc.info*. See http://gcc.gnu.org/bugs/ for how to report bugs usefully. Copyright years on GCC source files may be listed using range notation, e.g., 1987-2012, indicating that every year in the range, inclusive, is a copyrightable year that could otherwise be listed individually.