On Tue, 16 Jul 2013, Hendrik Greving wrote: > #include "tm_p.h" /* For TARGET_CPU_CPP_BUILTINS & friends. */ That comment is because the macro definition may call functions, whose prototypes are in tm_p.h. The macro is defined in tm.h (also included in c-cppbuiltin.c), and any functions it uses are prototyped in tm_p.h. -- Joseph S. Myers joseph@codesourcery.com