Eric, I just reran "make -k check RUNTESTFLAGS='--target_board "unix{-m64}"'" in the darwin_objdir/powerpc-apple-darwin8/libstdc++-v3 directory after applying the following patch to suppress the "can't find atom for N_GSYM stabs" ld64 linker warnings...
--- gcc-4.2-20060825/libstdc++-v3/testsuite/lib/prune.exp.org 2006-08-26 11:22:52.000000000 -0400 +++ gcc-4.2-20060825/libstdc++-v3/testsuite/lib/prune.exp 2006-08-26 11:23:39.000000000 -0400 @@ -29,5 +29,7 @@ regsub -all "(^|\n)\[^\n\]*: Additional NOP may be necessary to workaround Itanium processor A/B step errata" $text "" text regsub -all "(^|\n)\[^\n*\]*: Assembler messages:\[^\n\]*" $text "" text + regsub -all "(^|\n)can't find atom for N_GSYM stabs \[^\n\]* in \[^\n\]*" $text "" text + return $text } Once the noise from those linker warnings is removed from the libstdc++-v3 testsuite results at -m64 on Darwin PPC, we find that the failures drop from 54 to just 6. So we actually only have four additional libstdc++-v3 testsuite failures at -m64 compared to -m32. These are... FAIL: 21_strings/basic_string/cons/char/1.cc execution test FAIL: 21_strings/basic_string/cons/wchar_t/1.cc execution test FAIL: 21_strings/basic_string/insert/char/1.cc execution test FAIL: 21_strings/basic_string/insert/wchar_t/1.cc execution test which certainly would appear as if they are all related bugs. Can you try the above check on x86_64 and see how many regressions you have when the linker warnings suppressed? Jack ps Do you want to create a PR for these failures at -m64 or should I?