[PATCH] Fix test failure at -O0 by pruning output

[Jonathan Wakely]

        PR libstdc++/79323
        * testsuite/20_util/duration/literals/range.cc: Prune extra output
        at -O0.

Tested x86_64-linux, committed to trunk.


commit c090246da29b04f260a31886537f1e4790652f08
Author: Jonathan Wakely <jwak...@redhat.com>
Date:   Mon Feb 6 14:13:51 2017 +0000

    Fix test failure at -O0 by pruning output
    
        PR libstdc++/79323
        * testsuite/20_util/duration/literals/range.cc: Prune extra output
        at -O0.

diff --git a/libstdc++-v3/testsuite/20_util/duration/literals/range.cc 
b/libstdc++-v3/testsuite/20_util/duration/literals/range.cc
index 451d161..eafc806 100644
--- a/libstdc++-v3/testsuite/20_util/duration/literals/range.cc
+++ b/libstdc++-v3/testsuite/20_util/duration/literals/range.cc
@@ -28,3 +28,4 @@ test01()
   auto h = 9223372036854775808h;
   // { dg-error "cannot be represented" "" { target *-*-* } 890 }
 }
+// { dg-prune-output "in constexpr expansion" } // needed for -O0