[Bug c/96907] [docs] document builtins for fputc and putc
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96907
Martin Sebor changed:
What|Removed |Added
CC||msebor at gcc dot gnu.org
--- Comment #6 from Martin Sebor ---
Rather than en enumerating all the functions that are handled as built-ins (and
keeping them in sync with the code) it would be simpler to state that any
function prescribed by this or that revision of a standard may be implemented
as a built-in, and suggesting to use the __has_builtin() preprocessor function
to query support for each.
Besides adding attributes to their declarations, GCC transforms calls to some
of them into others (e.g., fputs to fputc, or fprintf to fputs or fputc) or
eliminated altogether (e.g., fputs("", f)). It might be helpful to mention
that in the manual and point users who want to avoid such transformations to
-fno-builtin-.
[Bug c/96907] [docs] document builtins for fputc and putc
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96907 --- Comment #5 from Nick Desaulniers --- No preferences either way. I was just comparing differences between compilers for __has_builtin and noticed GCC returns true for those two. Is that ok?
[Bug c/96907] [docs] document builtins for fputc and putc
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96907 Jakub Jelinek changed: What|Removed |Added CC||jakub at gcc dot gnu.org --- Comment #4 from Jakub Jelinek --- For various builtins it isn't merely about default attached attributes, but also about the compiler understanding what the function does in more detail and perhaps performing some optimizations on them, transform one function call into another one, or understand some aliasing etc. behavior of it. I'm not really sure it is a good idea to document it all.
[Bug c/96907] [docs] document builtins for fputc and putc
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96907 Segher Boessenkool changed: What|Removed |Added CC||segher at gcc dot gnu.org --- Comment #3 from Segher Boessenkool --- Many other "builtins" documented there are only ever implemented with libcalls as well?
[Bug c/96907] [docs] document builtins for fputc and putc
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96907 --- Comment #2 from Richard Biener --- They are not really "builtins", they are merely present to have default attributes attached to them.
[Bug c/96907] [docs] document builtins for fputc and putc
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96907 --- Comment #1 from Andrew Pinski --- putc was added by g-b53b5aa509 fputc has been there since before 2003.
