// RUN: %clang_cc1 -Wall -Wshift-sign-overflow -ffreestanding -fsyntax-only -verify %s #include <limits.h> #define WORD_BIT (sizeof(int) * CHAR_BIT) enum { X = 1 << 0, Y = 1 << 1, Z = 1 << 2 }; void test() { char c; c = 0 << 0; c = 0 << 1; c = 1 << 0; c = 1 << -0; c = 1 >> -0; c = 1 << -1; // expected-warning {{shift count is negative}} c = 1 >> -1; // expected-warning {{shift count is negative}} c = 1 << c; c <<= 0; c >>= 0; c <<= 1; c >>= 1; c <<= -1; // expected-warning {{shift count is negative}} c >>= -1; // expected-warning {{shift count is negative}} c <<= 999999; // expected-warning {{shift count >= width of type}} c >>= 999999; // expected-warning {{shift count >= width of type}} c <<= CHAR_BIT; // expected-warning {{shift count >= width of type}} c >>= CHAR_BIT; // expected-warning {{shift count >= width of type}} c <<= CHAR_BIT+1; // expected-warning {{shift count >= width of type}} c >>= CHAR_BIT+1; // expected-warning {{shift count >= width of type}} (void)((long)c << CHAR_BIT); int i; i = 1 << (WORD_BIT - 2); i = 2 << (WORD_BIT - 1); // expected-warning {{bits to represent, but 'int' only has}} i = 1 << (WORD_BIT - 1); // expected-warning {{sets the sign bit of the shift expression}} i = -1 << (WORD_BIT - 1); // expected-warning {{shifting a negative signed value is undefined}} i = -1 << 0; // expected-warning {{shifting a negative signed value is undefined}} i = 0 << (WORD_BIT - 1); i = (char)1 << (WORD_BIT - 2); unsigned u; u = 1U << (WORD_BIT - 1); u = 5U << (WORD_BIT - 1); long long int lli; lli = INT_MIN << 2; // expected-warning {{shifting a negative signed value is undefined}} lli = 1LL << (sizeof(long long) * CHAR_BIT - 2); } #define a 0 #define ashift 8 enum { b = (a << ashift) }; // Don't warn for negative shifts in code that is unreachable. void test_pr5544() { (void) (((1) > 63 && (1) < 128 ? (((unsigned long long) 1)<<((1)-64)) : (unsigned long long) 0)); // no-warning } void test_shift_too_much(char x) { if (0) (void) (x >> 80); // no-warning (void) (x >> 80); // expected-warning {{shift count >= width of type}} }