[gcc r12-5416] libstdc++, testsuite: Add a prune expression for external tool bug.

[Iain D Sandoe]

https://gcc.gnu.org/g:c7b782d847d8682af9d5d91c0614a880cc2436f1

commit r12-5416-gc7b782d847d8682af9d5d91c0614a880cc2436f1
Author: Iain Sandoe <iain@sandoe.co.uk>
Date:   Fri Nov 19 15:52:29 2021 +0000

    libstdc++, testsuite: Add a prune expression for external tool bug.
    
    Depending on the permutation of CPU, OS version and shared/non-
    shared library inclusion, we get can get warnings from the external
    tools (ld64, dsymutil) which are not actually libstdc++ issues but
    relate to the external tools themselves.  This is already pruned
    in the main testsuite, this adds it to the library.
    
    Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>
    
    libstdc++-v3/ChangeLog:
    
            * testsuite/lib/prune.exp: Prune dsymutil (ld64) warning.

Diff:
---
 libstdc++-v3/testsuite/lib/prune.exp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/libstdc++-v3/testsuite/lib/prune.exp b/libstdc++-v3/testsuite/lib/prune.exp
index 334f8218d16..41c4b51cb16 100644
--- a/libstdc++-v3/testsuite/lib/prune.exp
+++ b/libstdc++-v3/testsuite/lib/prune.exp
@@ -66,9 +66,12 @@ proc libstdc++-dg-prune { system text } {
     regsub -all "(^|\n)\[^\n\]*warning: DWARFDebugInfoEntry::AppendDependants\[^\n\]*AT_\[^\n\]*_bound\[^\n\]*FORM_ref4\[^\n\]*" $text "" text
     regsub -all "(^|\n)\[^\n\]*warning:\[^\n\]*TAG_variable:  AT_location\[^\n\]*didn't have valid function low pc\[^\n\]*" $text "" text
 
-    # Ignore harmless warnings from Xcode 4.0.
+    # Ignore harmless warnings from Xcode 4+.
     regsub -all "(^|\n)\[^\n\]*ld: warning: could not create compact unwind for\[^\n\]*" $text "" text
 
+    # Ignore dsymutil warning (tool bug is actually in the linker)
+    regsub -all "(^|\n)\[^\n\]*could not find object file symbol for symbol\[^\n\]*" $text "" text
+
     foreach p $additional_prunes {
 	if { [string length $p] > 0 } {
 	    # Following regexp matches a complete line containing $p.