Instead of relying on whether a certain identifier is a builtin, introduce BuiltinAttr to specify a declaration as having builtin semantics.
This fixes incompatible redeclarations of builtins, as reverting the identifier as being builtin due to one incompatible redeclaration would have broken rest of the builtin calls.
Mostly-compatible redeclarations of builtins also no longer have builtin semantics. They don't call the builtin nor inherit their attributes.
A long-standing FIXME regarding builtins inside a namespace enclosed in extern "C" not being recognized is also addressed.
Due to the more correct handling attributes for builtin functions are added in more places, resulting in more useful warnings.
Tests are updated to reflect that.
Intrinsics without an inline definition in intrin.h had `inline` and `static` removed as they had no effect and caused them to no longer be recognized as builtins otherwise.
A pthread_create() related test is XFAIL-ed, as it relied on it being recognized as a builtin based on its name.
The builtin declaration syntax is too restrictive and doesn't allow custom structs, function pointers, etc.
It seems to be the only case and fixing this would require reworking the current builtin syntax, so this seems acceptable.
Fixes PR45410.
Reviewed By: rsmith, yutsumi
Differential Revision: https://reviews.llvm.org/D77491
Implement a pessimistic evaluator of the minimal required size for a buffer
based on the format string, and couple that with the fortified version to emit a
warning when the buffer size is lower than the lower bound computed from the
format string.
Differential Revision: https://reviews.llvm.org/D71566
This fixes a false positive on the following, where st is configured to have
different sizes based on some preprocessor logic:
if (sizeof(buf) == sizeof(*st))
memcpy(&buf, st, sizeof(*st));
llvm-svn: 357041
These diagnose overflowing calls to subset of fortifiable functions. Some
functions, like sprintf or strcpy aren't supported right not, but we should
probably support these in the future. We previously supported this kind of
functionality with -Wbuiltin-memcpy-chk-size, but that diagnostic doesn't work
with _FORTIFY implementations that use wrapper functions. Also unlike that
diagnostic, we emit these warnings regardless of whether _FORTIFY_SOURCE is
actually enabled, which is nice for programs that don't enable the runtime
checks.
Why not just use diagnose_if, like Bionic does? We can get better diagnostics in
the compiler (i.e. mention the sizes), and we have the potential to diagnose
sprintf and strcpy which is impossible with diagnose_if (at least, in languages
that don't support C++14 constexpr). This approach also saves standard libraries
from having to add diagnose_if.
rdar://48006655
Differential revision: https://reviews.llvm.org/D58797
llvm-svn: 356397
Michael Benfield