llvm-project/clang/test/Sema/builtins-overflow.c
Aaron Ballman 6c75ab5f66 Introduce _BitInt, deprecate _ExtInt
WG14 adopted the _ExtInt feature from Clang for C23, but renamed the
type to be _BitInt. This patch does the vast majority of the work to
rename _ExtInt to _BitInt, which accounts for most of its size. The new
type is exposed in older C modes and all C++ modes as a conforming
extension. However, there are functional changes worth calling out:

* Deprecates _ExtInt with a fix-it to help users migrate to _BitInt.
* Updates the mangling for the type.
* Updates the documentation and adds a release note to warn users what
is going on.
* Adds new diagnostics for use of _BitInt to call out when it's used as
a Clang extension or as a pre-C23 compatibility concern.
* Adds new tests for the new diagnostic behaviors.

I want to call out the ABI break specifically. We do not believe that
this break will cause a significant imposition for early adopters of
the feature, and so this is being done as a full break. If it turns out
there are critical uses where recompilation is not an option for some
reason, we can consider using ABI tags to ease the transition.
2021-12-06 12:52:01 -05:00

42 lines
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C

// RUN: %clang_cc1 -fsyntax-only -verify %s
#if __has_feature(__builtin_add_overflow)
#warning defined as expected
// expected-warning@-1 {{defined as expected}}
#endif
void test(void) {
unsigned r;
const char * c;
float f;
const unsigned q;
__builtin_add_overflow(); // expected-error {{too few arguments to function call, expected 3, have 0}}
__builtin_add_overflow(1, 1, 1, 1); // expected-error {{too many arguments to function call, expected 3, have 4}}
__builtin_add_overflow(c, 1, &r); // expected-error {{operand argument to overflow builtin must be an integer ('const char *' invalid)}}
__builtin_add_overflow(1, c, &r); // expected-error {{operand argument to overflow builtin must be an integer ('const char *' invalid)}}
__builtin_add_overflow(1, 1, 3); // expected-error {{result argument to overflow builtin must be a pointer to a non-const integer ('int' invalid)}}
__builtin_add_overflow(1, 1, &f); // expected-error {{result argument to overflow builtin must be a pointer to a non-const integer ('float *' invalid)}}
__builtin_add_overflow(1, 1, &q); // expected-error {{result argument to overflow builtin must be a pointer to a non-const integer ('const unsigned int *' invalid)}}
{
_BitInt(128) x = 1;
_BitInt(128) y = 1;
_BitInt(128) result;
_Bool status = __builtin_mul_overflow(x, y, &result); // expect ok
}
{
unsigned _BitInt(129) x = 1;
unsigned _BitInt(129) y = 1;
unsigned _BitInt(129) result;
_Bool status = __builtin_mul_overflow(x, y, &result); // expect ok
}
{
_BitInt(129) x = 1;
_BitInt(129) y = 1;
_BitInt(129) result;
_Bool status = __builtin_mul_overflow(x, y, &result); // expected-error {{__builtin_mul_overflow does not support 'signed _BitInt' operands of more than 128 bits}}
}
}