This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: Unused GCC builtins
- From: Florian Weimer <fw at deneb dot enyo dot de>
- To: "Manuel Rigger" <manuel dot rigger at jku dot at>
- Cc: <gcc at gcc dot gnu dot org>, <s dot marr at kent dot ac dot uk>, <bram dot adams at polymtl dot ca>
- Date: Mon, 22 Jan 2018 19:29:28 +0100
- Subject: Re: Unused GCC builtins
- Authentication-results: sourceware.org; auth=none
- References: <5A66076F0200008100014BC3@s05gw02.im.jku.at>
* Manuel Rigger:
> Details: We downloaded all C projects from GitHub that had more than 80
> GitHub stars, which yielded almost 5,000 projects with a total of more
> than one billion lines of C code. We filtered GCC, forks of GCC, and
> other compilers as we did not want to incorporate internal usages of GCC
> builtins or test cases. We extracted all builtin names from the GCC
> docs, and also tried to find such names in the source code, which we
> considered as builtin usages.
You actually need to compile the sources with an instrumented compiler
to discover uses of built-ins. Not all references will have verbatim,
textual references in source code, but their names are constructed
using preprocessor macros. This happens for the majority of the
floating-point-related built-ins you listed, I think.