[gcc r12-6531] libstdc++: Add explicit dg-do directive to .../103955.cc

[Patrick Palka]

https://gcc.gnu.org/g:acc38526f6c74ad3540ecaa950f1d3c44f87d345

commit r12-6531-gacc38526f6c74ad3540ecaa950f1d3c44f87d345
Author: Patrick Palka <ppalka@redhat.com>
Date:   Wed Jan 12 11:39:48 2022 -0500

    libstdc++: Add explicit dg-do directive to .../103955.cc
    
    libstdc++-v3/ChangeLog:
    
            * testsuite/20_util/to_chars/103955.cc: Add explicit dg-do
            directive.

Diff:
---
 libstdc++-v3/testsuite/20_util/to_chars/103955.cc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/libstdc++-v3/testsuite/20_util/to_chars/103955.cc b/libstdc++-v3/testsuite/20_util/to_chars/103955.cc
index 3753c87ad8b..e7f17f7a9e8 100644
--- a/libstdc++-v3/testsuite/20_util/to_chars/103955.cc
+++ b/libstdc++-v3/testsuite/20_util/to_chars/103955.cc
@@ -1,6 +1,7 @@
 // PR libstdc++/103955
 // Verify we don't crash when the floating-point to_chars overloads are passed
 // a large precision argument.
+// { dg-do run { target c++17 } }
 
 #include <charconv>