[gcc r12-1132] PR testsuite/100749 - gcc.dg/pch/valid-1.c fails after r12-949

[Indu Bhagat <ibhagat@gcc.gnu.org>]

https://gcc.gnu.org/g:a87efd32384ee78ee33d20703deaa65fba81cb2d

commit r12-1132-ga87efd32384ee78ee33d20703deaa65fba81cb2d
Author: Indu Bhagat <indu.bhagat@oracle.com>
Date:   Mon May 31 09:19:38 2021 -0700

    PR testsuite/100749 - gcc.dg/pch/valid-1.c fails after r12-949
    
    Fix failing pch testcases. Use xstrdup to retain a reliable copy of the debug
    format str containing the names (df_set_names is a static string var).
    
    2021-05-31  Indu Bhagat  <indu.bhagat@oracle.com>
    
    gcc/c-family/
            PR testsuite/100749
            * c-pch.c (c_common_valid_pch): Use xstrdup for debug format set names.

Diff:
---
 gcc/c-family/c-pch.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/gcc/c-family/c-pch.c b/gcc/c-family/c-pch.c
index 8f0f76024a2..5da60423354 100644
--- a/gcc/c-family/c-pch.c
+++ b/gcc/c-family/c-pch.c
@@ -255,10 +255,13 @@ c_common_valid_pch (cpp_reader *pfile, const char *name, int fd)
   if (v.pch_write_symbols != write_symbols
       && write_symbols != NO_DEBUG)
     {
+      char *created_str = xstrdup (debug_set_names (v.pch_write_symbols));
+      char *used_str = xstrdup (debug_set_names (write_symbols));
       cpp_warning (pfile, CPP_W_INVALID_PCH,
 		   "%s: created with '%s' debug info, but used with '%s'", name,
-		   debug_set_names (v.pch_write_symbols),
-		   debug_set_names (write_symbols));
+		   created_str, used_str);
+      free (created_str);
+      free (used_str);
       return 2;
     }