PR target/79127

[thirdparty/gcc.git] / libgfortran / acinclude.m4

diff --git a/libgfortran/acinclude.m4 b/libgfortran/acinclude.m4
index 9a7f461af3c4f362a13719d1959c511722d04d13..34e14071aebd996d07dc248ac2a0eb2ebe5a8254 100644 (file)
--- a/libgfortran/acinclude.m4
+++ b/libgfortran/acinclude.m4
@@ -437,7 +437,14 @@ AC_DEFUN([LIBGFOR_CHECK_AVX512F], [
        typedef double __m512d __attribute__ ((__vector_size__ (64)));
        __m512d _mm512_add (__m512d a)
        {
-         return __builtin_ia32_addpd512_mask (a, a, a, 1, 4);
+         __m512d b = __builtin_ia32_addpd512_mask (a, a, a, 1, 4);
+         /* For -m64/-mx32 also verify that code will work even if
+            the target uses call saved zmm16+ and needs to emit
+            unwind info for them (e.g. on mingw).  See PR79127.  */
+#ifdef __x86_64__
+         asm volatile ("" : : : "zmm16", "zmm17", "zmm18", "zmm19");
+#endif
+         return b;
         }]], [[]])],
        AC_DEFINE(HAVE_AVX512F, 1,
        [Define if AVX512f instructions can be compiled.]),