http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50685
--- Comment #5 from David Edelsohn <dje at gcc dot gnu.org> 2011-10-10 19:00:22 UTC --- AIX 5.3 TL10 (as well as AIX 6.1 TL05 and AIX 7.1 TL00) instroduced AIX assembler changes with some bugs. An AIX iFix for AIX 5.3 is available (APAR IZ98385 for AIX 5.3 TL10, APAR IZ98477 for AIX 5.3 TL11 and IZ98134 for AIX 5.3 TL12). I know the assembler fixes address another bug with the assembler generating corrupt object files, but I do not know if it fixes this bug of the assembler crashing. This is an AIX bug and you need to contact AIX Customer Support.