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| author | Eric Botcazou <ebotcazou@adacore.com> | 2021-05-04 12:40:42 +0200 |
|---|---|---|
| committer | Eric Botcazou <ebotcazou@adacore.com> | 2021-05-04 12:53:21 +0200 |
| commit | f418bc3cd173bc4e679469928d4d96ffcc05fc7e (patch) | |
| tree | 9883221a26c13694cf41f221dddf3f4ac2fc9acc /libiberty/configure.ac | |
| parent | 1b0f570009825ce53a3967ea9a92b1961b7c122b (diff) | |
| download | gcc-f418bc3cd173bc4e679469928d4d96ffcc05fc7e.tar.gz | |
Fix libiberty link failures in LTO mode for MinGW
The test for the presence of variables (really symbols) does not work
when you add -Ox -flto to CFLAGS:
for v in $vars; do
AC_MSG_CHECKING([for $v])
AC_CACHE_VAL(libiberty_cv_var_$v,
[AC_LINK_IFELSE([AC_LANG_PROGRAM([[int *p;]],[[extern int $v [];
p = $v;]])],
[eval "libiberty_cv_var_$v=yes"],
[eval "libiberty_cv_var_$v=no"])])
if eval "test \"`echo '$libiberty_cv_var_'$v`\" = yes"; then
AC_MSG_RESULT(yes)
AC_DEFINE_UNQUOTED($n)
else
AC_MSG_RESULT(no)
fi
done
because the assignment to 'p' is optimized away by LTO. This is visible
on MinGW platforms in the form of a link failure for sys_siglist.
There is another link failures for stpcpy: the symbol is both referenced
by libiberty's pex-win32.c and provided by libiberty's stpcpy.c, so it
needs to have a linkage to be resolved in LTO mode.
libiberty/
* configure.ac: Make test for variables more robust.
* configure: Regenerate.
gcc/
* builtins.c (builtin_with_linkage_p): Return true for stp[n]cpy.
* symtab.c (symtab_node::output_to_lto_symbol_table_p): Tidy up.
Diffstat (limited to 'libiberty/configure.ac')
| -rw-r--r-- | libiberty/configure.ac | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/libiberty/configure.ac b/libiberty/configure.ac index ad952963971..3c03f24d368 100644 --- a/libiberty/configure.ac +++ b/libiberty/configure.ac @@ -665,7 +665,7 @@ if test -z "${setobjs}"; then for v in $vars; do AC_MSG_CHECKING([for $v]) AC_CACHE_VAL(libiberty_cv_var_$v, - [AC_LINK_IFELSE([AC_LANG_PROGRAM([[int *p;]],[[extern int $v []; p = $v;]])], + [AC_LINK_IFELSE([AC_LANG_PROGRAM([[extern int $v [];]],[[if ($v [0]) return 1;]])], [eval "libiberty_cv_var_$v=yes"], [eval "libiberty_cv_var_$v=no"])]) if eval "test \"`echo '$libiberty_cv_var_'$v`\" = yes"; then |