1 /* Test for diagnostics for constant overflow. */
2 /* Origin: Joseph Myers <joseph@codesourcery.com> */
3 /* { dg-do compile } */
4 /* { dg-options "-std=c99" } */
10 /* Unsigned overflow wraps around. */
12 /* Overflow in an unevaluated part of an expression is OK (example
15 E3 = 1 / 0, /* { dg-warning "division by zero" } */
16 /* { dg-error "enumerator value for 'E3' is not an integer constant" "enum error" { target *-*-* } 15 } */
17 /* But as in DR#031, the 1/0 in an evaluated subexpression means the
18 whole expression violates the constraints. */
19 E4 = 0 * (1 / 0), /* { dg-warning "division by zero" } */
20 /* { dg-error "enumerator value for 'E4' is not an integer constant" "enum error" { target *-*-* } 19 } */
21 E5 = INT_MAX + 1, /* { dg-warning "integer overflow in expression" } */
22 /* Again, overflow in evaluated subexpression. */
23 E6 = 0 * (INT_MAX + 1), /* { dg-warning "integer overflow in expression" } */
24 /* A cast does not constitute overflow in conversion. */
30 int : 0 * (1 / 0); /* { dg-warning "division by zero" } */
31 /* { dg-error "not an integer constant" "integer constant" { target *-*-* } 30 } */
32 int : 0 * (INT_MAX + 1); /* { dg-warning "integer overflow in expression" } */
38 /* This expression is not required to be a constant expression, so
39 it should just involve undefined behavior at runtime. */
40 int c = INT_MAX + 1; /* { dg-warning "integer overflow in expression" } */
43 /* But this expression does need to be constant. */
44 static int sc = INT_MAX + 1; /* { dg-warning "integer overflow in expression" } */
46 /* The first two of these involve overflow, so are not null pointer
47 constants. The third has the overflow in an unevaluated
48 subexpression, so is a null pointer constant. */
49 void *p = 0 * (INT_MAX + 1); /* { dg-warning "integer overflow in expression" } */
50 /* { dg-warning "initialization makes pointer from integer without a cast" "null" { target *-*-* } 49 } */
51 void *q = 0 * (1 / 0); /* { dg-warning "division by zero" } */
52 /* { dg-error "initializer element is not constant" "constant" { target *-*-* } 51 } */
53 /* { dg-warning "initialization makes pointer from integer without a cast" "null" { target *-*-* } 51 } */
54 void *r = (1 ? 0 : INT_MAX+1);
61 case 0 * (1/0): /* { dg-warning "division by zero" } */
62 /* { dg-error "case label does not reduce to an integer constant" "constant" { target *-*-* } 61 } */
64 case 1 + 0 * (INT_MAX + 1): /* { dg-warning "integer overflow in expression" } */
72 return INT_MAX + 1; /* { dg-warning "integer overflow in expression" } */
78 return INT_MAX + 1 - INT_MAX; /* { dg-warning "integer overflow in expression" } */
81 void fuc (unsigned char);
82 void fsc (signed char);
88 fsc (SCHAR_MIN - 1); /* { dg-warning "overflow in implicit constant conversion" } */
90 fsc (UCHAR_MAX + 1); /* { dg-warning "overflow in implicit constant conversion" } */
92 fuc (UCHAR_MAX + 1); /* { dg-warning "large integer implicitly truncated to unsigned type" } */
94 fuc (SCHAR_MIN - 1); /* { dg-warning "large integer implicitly truncated to unsigned type" } */
95 fuc (-UCHAR_MAX); /* { dg-warning "large integer implicitly truncated to unsigned type" } */
98 void fui (unsigned int);
99 void fsi (signed int);
107 /* For some reason, we only give certain warnings for implicit
108 conversions among values of the same precision with -Wconversion,
109 while we don't give others at all. */
110 fsi ((unsigned)INT_MAX + 1);
111 si = (unsigned)INT_MAX + 1;
112 si = x ? (unsigned)INT_MAX + 1 : 1;
113 fsi ((unsigned)INT_MAX + 2);
114 si = (unsigned)INT_MAX + 2;
115 si = x ? (unsigned)INT_MAX + 2 : 1;
123 ui = x ? INT_MIN : 1U;