Filter out unknown symbols in stack-protector test.

1 files changed, 7 insertions, 0 deletions

diff --git a/configure.in b/configure.in
index a9ee7334d6..38b55a6784 100644
--- a/configure.in
+++ b/configure.in
@@ -2072,6 +2072,13 @@ libc_undefs=`$NM -u conftest.o |
   AC_MSG_ERROR([confusing output from $NM -u])
 }
 echo >&AS_MESSAGE_LOG_FD "libc_undefs='$libc_undefs'"
+# On some architectures, there are architecture-specific undefined
+# symbols (resolved by the linker), so filter out unknown symbols.
+# This will fail to produce the correct result if the compiler
+# defaults to -fstack-protector but this produces an undefined symbol
+# other than __stack_chk_fail.  However, compilers like that have not
+# been encountered in practice.
+libc_undefs=`echo "$libc_undefs" | egrep '^(foobar|__stack_chk_fail)$'`
 case "$libc_undefs" in
 foobar) libc_cv_predef_stack_protector=no ;;
 '__stack_chk_fail