In gcc4 only djgpp and cygming targets have HANDLE_PRAGMA_PACK_PUSH_POP defined, the gcc4 documentation does not say these #pragmas are target spesific, there is also no configure option to enable this for other (e.g *-elf) targets.
-- Summary: HANDLE_PRAGMA_PACK_PUSH_POP not a configure option or documented correctly Product: gcc Version: 4.0.0 Status: UNCONFIRMED Severity: normal Priority: P2 Component: preprocessor AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: mfletcher at serck-controls dot co dot uk CC: gcc-bugs at gcc dot gnu dot org GCC host triplet: i686-host_pc-linux-gnu GCC target triplet: i486-unknown-elf http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20137