https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103622
--- Comment #3 from Kewen Lin <linkw at gcc dot gnu.org> ---
> One thought seems to check instance->fntype first and take (skip) it as
> mismatch if it's NULL.
This looks like a bad idea, to use long double as the type instead of float128
when type float128 isn't supported might be better.
diff --git a/gcc/config/rs6000/rs6000-gen-builtins.c
b/gcc/config/rs6000/rs6000-gen-builtins.c
index d2e9c4ce547..2b87eef1412 100644
--- a/gcc/config/rs6000/rs6000-gen-builtins.c
+++ b/gcc/config/rs6000/rs6000-gen-builtins.c
@@ -2473,6 +2473,39 @@ write_fntype_init (char *str)
fprintf (init_file, ",\n\t\t\t\t");
}
fprintf (init_file, "NULL_TREE);\n");
+
+ /* Use long_double_type_node instead if float128_type_node isn't
+ supported, it's to avoid unexpected function types. */
+ if (tf_found)
+ {
+ char *buf1 = strdup (str);
+ fprintf (init_file, " else\n ");
+ fprintf (init_file, " %s\n = build_function_type_list (", buf1);
+ tok = strtok (buf1, "_");
+ if (!strcmp ("tf", tok))
+ write_type_node ("ld", true);
+ else
+ write_type_node (tok, true);
+ tok = strtok (0, "_");
+ tok = strtok (0, "_");
+ if (tok)
+ fprintf (init_file, ",\n\t\t\t\t");
+
+ /* Note: A function with no arguments ends with '_ftype_v'. */
+ while (tok && strcmp (tok, "v"))
+ {
+ if (!strcmp ("tf", tok))
+ write_type_node ("ld", true);
+ else
+ write_type_node (tok, true);
+ tok = strtok (0, "_");
+ fprintf (init_file, ",\n\t\t\t\t");
+ }
+ fprintf (init_file, "NULL_TREE);\n");
+
+ free (buf1);
+ }
+
free (buf);
}
The above hacking make the segfault gone and it will emit:
test.c: In function ‘get_float128_exponent’:
test.c:6:5: error: ‘__builtin_vsx_scalar_extract_expq’ requires ISA 3.0 IEEE
128-bit floating point
6 | return __builtin_vec_scalar_extract_exp (a);
| ^~~~~~
test.c:6:5: note: overloaded builtin ‘__builtin_vec_scalar_extract_exp’ is
implemented by builtin ‘__builtin_vsx_scalar_extract_expq’
