/* RUN: %clang_cc1 -std=c99 -ffreestanding -triple x86_64-unknown-linux -fsyntax-only -verify -pedantic -Wno-c11-extensions %s RUN: %clang_cc1 -std=c99 -ffreestanding -triple x86_64-unknown-win32 -fms-compatibility -fsyntax-only -verify -pedantic -Wno-c11-extensions %s RUN: %clang_cc1 -std=c11 -ffreestanding -fsyntax-only -verify -pedantic %s RUN: %clang_cc1 -std=c17 -ffreestanding -fsyntax-only -verify -pedantic %s RUN: %clang_cc1 -std=c2x -ffreestanding -fsyntax-only -verify -pedantic %s */ /* WG14 DR209: partial * Problem implementing INTN_C macros */ #include #if INT8_C(0) != 0 #error "uh oh" #elif INT16_C(0) != 0 #error "uh oh" #elif INT32_C(0) != 0 #error "uh oh" #elif INT64_C(0) != 0LL #error "uh oh" #elif UINT8_C(0) != 0U #error "uh oh" #elif UINT16_C(0) != 0U #error "uh oh" #elif UINT32_C(0) != 0U #error "uh oh" #elif UINT64_C(0) != 0ULL #error "uh oh" #endif void dr209(void) { (void)_Generic(INT8_C(0), __typeof__(+(int_least8_t){0}) : 1); (void)_Generic(INT16_C(0), __typeof__(+(int_least16_t){0}) : 1); (void)_Generic(INT32_C(0), __typeof__(+(int_least32_t){0}) : 1); (void)_Generic(INT64_C(0), __typeof__(+(int_least64_t){0}) : 1); // FIXME: This is not the expected behavior; the type of the expanded value // in both of these cases should be 'int', // // C99 7.18.4p3: The type of the expression shall have the same type as would // an expression of the corresponding type converted according to the integer // promotions. // // C99 7.18.4.1p1: The macro UINTN_C(value) shall expand to an integer // constant expression corresponding to the type uint_leastN_t. // // C99 7.18.1.2p2: The typedef name uint_leastN_t designates an unsigned // integer type with a width of at least N, ... // // So the value's type is the same underlying type as uint_leastN_t, which is // unsigned char for uint_least8_t, and unsigned short for uint_least16_t, // but then the value undergoes integer promotions which would convert both // of those types to int. // (void)_Generic(UINT8_C(0), __typeof__(+(uint_least8_t){0}) : 1); (void)_Generic(UINT16_C(0), __typeof__(+(uint_least16_t){0}) : 1); // expected-error@-2 {{controlling expression type 'unsigned int' not compatible with any generic association type}} // expected-error@-2 {{controlling expression type 'unsigned int' not compatible with any generic association type}} (void)_Generic(UINT32_C(0), __typeof__(+(uint_least32_t){0}) : 1); (void)_Generic(UINT64_C(0), __typeof__(+(uint_least64_t){0}) : 1); }