Add va_start()/va_copy()/va_end to Builtins.def

[thakis]

Summary

That way, clang suggests including stdarg.h when these are used in C files.

[hans]

lgtm

Seems that some of these are tested in Sema/implicit-builtin-decl.c, but it doesn't look exhaustive and I'm not sure it's worth adding these.

[thakis]

r322573, thanks!

Yes, I looked at the same file and came to the same conclusion regarding a test :-)

include/clang/Basic/Builtins.def

 LANGBUILTIN(_rotr64, "ULLiULLii", "n", ALL_MS_LANGUAGES)
 LANGBUILTIN(__va_start,       "vc**.", "nt", ALL_MS_LANGUAGES)
 LANGBUILTIN(__fastfail, "vUi",    "nr", ALL_MS_LANGUAGES)
 
 // Microsoft library builtins.
 LIBBUILTIN(_setjmpex, "iJ", "fj",   "setjmpex.h", ALL_MS_LANGUAGES)
 
 // C99 library functions
+// C99 stdarg.h
+LIBBUILTIN(va_start, "vA.",       "fnt",   "stdarg.h", ALL_LANGUAGES)
+LIBBUILTIN(va_end, "vA",          "fn",    "stdarg.h", ALL_LANGUAGES)
+LIBBUILTIN(va_copy, "vAA",        "fn",    "stdarg.h", ALL_LANGUAGES)
 // C99 stdlib.h
 LIBBUILTIN(abort, "v",            "fr",    "stdlib.h", ALL_LANGUAGES)
 LIBBUILTIN(calloc, "v*zz",        "f",     "stdlib.h", ALL_LANGUAGES)
 LIBBUILTIN(exit, "vi",            "fr",    "stdlib.h", ALL_LANGUAGES)
 LIBBUILTIN(_Exit, "vi",           "fr",    "stdlib.h", ALL_LANGUAGES)
 LIBBUILTIN(malloc, "v*z",         "f",     "stdlib.h", ALL_LANGUAGES)
 LIBBUILTIN(realloc, "v*v*z",      "f",     "stdlib.h", ALL_LANGUAGES)
 // C99 string.h