diff options
Diffstat (limited to 'gcc/configure.ac')
| -rw-r--r-- | gcc/configure.ac | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/gcc/configure.ac b/gcc/configure.ac index 1676c40..67973b1 100644 --- a/gcc/configure.ac +++ b/gcc/configure.ac @@ -3202,6 +3202,19 @@ foo: nop rm -f conftest], [AC_DEFINE(HAVE_GAS_PE_SECREL32_RELOC, 1, [Define if your assembler and linker support 32-bit section relative relocs via '.secrel32 label'.])]) + # Test if the assembler supports the extended form of the .section + # directive that specifies section alignment. LTO support uses this, + # but normally only after installation, so we warn but don't fail the + # configure if LTO is enabled but the assembler does not support it. + gcc_GAS_CHECK_FEATURE([.section with alignment], gcc_cv_as_section_has_align, + [2,20,1],-fatal-warnings,[.section lto_test,"dr0"]) + if test x$gcc_cv_as_section_has_align != xyes; then + case ",$enable_languages," in + *,lto,*) + AC_MSG_WARN([LTO for $target requires binutils >= 2.20.1, but version found appears insufficient; LTO will not work until binutils is upgraded.]) + ;; + esac + fi ;; esac @@ -4270,6 +4283,17 @@ changequote([,])dnl AC_DEFINE(ENABLE_LTO, 1, [Define to enable LTO support.]) enable_lto=yes AC_SUBST(enable_lto) + # LTO needs to speak the platform's object file format, and has a + # number of implementations of the required binary file access APIs. + # ELF is the most common, and default. We only link libelf if ELF + # is indeed the selected format. + LTO_BINARY_READER=${lto_binary_reader} + LTO_USE_LIBELF=-lelf + if test "x$lto_binary_reader" != "xlto-elf" ; then + LTO_USE_LIBELF= + fi + AC_SUBST(LTO_BINARY_READER) + AC_SUBST(LTO_USE_LIBELF) ;; *) ;; esac |