http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55594
--- Comment #3 from David Edelsohn <dje at gcc dot gnu.org> 2012-12-06 19:25:05 UTC --- AIX as manual: -n Name Specifies the name that appears in the header of the assembler listing. By default, the header contains the name of the assembler source file. -Wa,-nH creates some confusing, inconsistent information for debugging and object file analysis. Because I do not spend a lot of time debugging libstdc++, I had not noticed it. I am glad that you are feeling better.