On Sep 29 2018, bx L <lbxlbxlbxlbx...@gmail.com> wrote: > I notice that gcc has some predefined macros, which can be > obtained with " gcc -dM -E - < /dev/null". I guess many of them are > machine-specified, such as __LDBL_MANT_DIG__. However, I can't find > where these macros are defined when browsing GCC's source codes. I'm > very curious about how these macros are defined.
Look for builtin_define, then inspect the context to see where the macro names are constructed. For example, c-family/c-cppbuiltin.c has a lot of them. Andreas. -- Andreas Schwab, sch...@linux-m68k.org GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1 "And now for something completely different."
