1*f4a2713aSLionel Sambuc // RUN: %clang -Wall -Wshift-sign-overflow -ffreestanding -fsyntax-only -Xclang -verify %s 2*f4a2713aSLionel Sambuc 3*f4a2713aSLionel Sambuc #include <limits.h> 4*f4a2713aSLionel Sambuc 5*f4a2713aSLionel Sambuc #define WORD_BIT (sizeof(int) * CHAR_BIT) 6*f4a2713aSLionel Sambuc 7*f4a2713aSLionel Sambuc enum { 8*f4a2713aSLionel Sambuc X = 1 << 0, 9*f4a2713aSLionel Sambuc Y = 1 << 1, 10*f4a2713aSLionel Sambuc Z = 1 << 2 11*f4a2713aSLionel Sambuc }; 12*f4a2713aSLionel Sambuc 13*f4a2713aSLionel Sambuc void test() { 14*f4a2713aSLionel Sambuc char c; 15*f4a2713aSLionel Sambuc 16*f4a2713aSLionel Sambuc c = 0 << 0; 17*f4a2713aSLionel Sambuc c = 0 << 1; 18*f4a2713aSLionel Sambuc c = 1 << 0; 19*f4a2713aSLionel Sambuc c = 1 << -0; 20*f4a2713aSLionel Sambuc c = 1 >> -0; 21*f4a2713aSLionel Sambuc c = 1 << -1; // expected-warning {{shift count is negative}} 22*f4a2713aSLionel Sambuc c = 1 >> -1; // expected-warning {{shift count is negative}} 23*f4a2713aSLionel Sambuc c = 1 << c; 24*f4a2713aSLionel Sambuc c <<= 0; 25*f4a2713aSLionel Sambuc c >>= 0; 26*f4a2713aSLionel Sambuc c <<= 1; 27*f4a2713aSLionel Sambuc c >>= 1; 28*f4a2713aSLionel Sambuc c <<= -1; // expected-warning {{shift count is negative}} 29*f4a2713aSLionel Sambuc c >>= -1; // expected-warning {{shift count is negative}} 30*f4a2713aSLionel Sambuc c <<= 999999; // expected-warning {{shift count >= width of type}} 31*f4a2713aSLionel Sambuc c >>= 999999; // expected-warning {{shift count >= width of type}} 32*f4a2713aSLionel Sambuc c <<= CHAR_BIT; // expected-warning {{shift count >= width of type}} 33*f4a2713aSLionel Sambuc c >>= CHAR_BIT; // expected-warning {{shift count >= width of type}} 34*f4a2713aSLionel Sambuc c <<= CHAR_BIT+1; // expected-warning {{shift count >= width of type}} 35*f4a2713aSLionel Sambuc c >>= CHAR_BIT+1; // expected-warning {{shift count >= width of type}} 36*f4a2713aSLionel Sambuc (void)((long)c << CHAR_BIT); 37*f4a2713aSLionel Sambuc 38*f4a2713aSLionel Sambuc int i; 39*f4a2713aSLionel Sambuc i = 1 << (WORD_BIT - 2); 40*f4a2713aSLionel Sambuc i = 2 << (WORD_BIT - 1); // expected-warning {{bits to represent, but 'int' only has}} 41*f4a2713aSLionel Sambuc i = 1 << (WORD_BIT - 1); // expected-warning {{sets the sign bit of the shift expression}} 42*f4a2713aSLionel Sambuc i = -1 << (WORD_BIT - 1); 43*f4a2713aSLionel Sambuc i = 0 << (WORD_BIT - 1); 44*f4a2713aSLionel Sambuc i = (char)1 << (WORD_BIT - 2); 45*f4a2713aSLionel Sambuc 46*f4a2713aSLionel Sambuc unsigned u; 47*f4a2713aSLionel Sambuc u = 1U << (WORD_BIT - 1); 48*f4a2713aSLionel Sambuc u = 5U << (WORD_BIT - 1); 49*f4a2713aSLionel Sambuc 50*f4a2713aSLionel Sambuc long long int lli; 51*f4a2713aSLionel Sambuc lli = INT_MIN << 2; // expected-warning {{bits to represent, but 'int' only has}} 52*f4a2713aSLionel Sambuc lli = 1LL << (sizeof(long long) * CHAR_BIT - 2); 53*f4a2713aSLionel Sambuc } 54*f4a2713aSLionel Sambuc 55*f4a2713aSLionel Sambuc #define a 0 56*f4a2713aSLionel Sambuc #define ashift 8 57*f4a2713aSLionel Sambuc enum { b = (a << ashift) }; 58*f4a2713aSLionel Sambuc 59*f4a2713aSLionel Sambuc // Don't warn for negative shifts in code that is unreachable. 60*f4a2713aSLionel Sambuc void test_pr5544() { 61*f4a2713aSLionel Sambuc (void) (((1) > 63 && (1) < 128 ? (((unsigned long long) 1)<<((1)-64)) : (unsigned long long) 0)); // no-warning 62*f4a2713aSLionel Sambuc } 63*f4a2713aSLionel Sambuc 64*f4a2713aSLionel Sambuc void test_shift_too_much(char x) { 65*f4a2713aSLionel Sambuc if (0) 66*f4a2713aSLionel Sambuc (void) (x >> 80); // no-warning 67*f4a2713aSLionel Sambuc (void) (x >> 80); // expected-warning {{shift count >= width of type}} 68*f4a2713aSLionel Sambuc } 69