| /* Test for diagnostics for constant overflow. Test with -pedantic-errors. */ |
| /* Origin: Joseph Myers <joseph@codesourcery.com> */ |
| /* { dg-do compile } */ |
| /* { dg-options "-std=c99 -pedantic-errors" } */ |
| |
| #include <limits.h> |
| |
| enum e { |
| E0 = INT_MAX, |
| /* Unsigned overflow wraps around. */ |
| E1 = UINT_MAX + 1, |
| /* Overflow in an unevaluated part of an expression is OK (example |
| in the standard). */ |
| E2 = 2 || 1 / 0, |
| E3 = 1 / 0, /* { dg-warning "warning: division by zero" } */ |
| /* { dg-error "error: enumerator value for 'E3' is not an integer constant" "enum error" { target *-*-* } 15 } */ |
| /* But as in DR#031, the 1/0 in an evaluated subexpression means the |
| whole expression violates the constraints. */ |
| E4 = 0 * (1 / 0), /* { dg-warning "warning: division by zero" } */ |
| /* { dg-error "error: enumerator value for 'E4' is not an integer constant" "enum error" { xfail *-*-* } 19 } */ |
| E5 = INT_MAX + 1, /* { dg-warning "warning: integer overflow in expression" } */ |
| /* { dg-error "error: overflow in constant expression" "constant" { target *-*-* } 21 } */ |
| /* Again, overflow in evaluated subexpression. */ |
| E6 = 0 * (INT_MAX + 1), /* { dg-warning "warning: integer overflow in expression" } */ |
| /* { dg-error "error: overflow in constant expression" "constant" { target *-*-* } 24 } */ |
| /* A cast does not constitute overflow in conversion. */ |
| E7 = (char) INT_MAX |
| }; |
| |
| struct s { |
| int a; |
| int : 0 * (1 / 0); /* { dg-warning "warning: division by zero" } */ |
| int : 0 * (INT_MAX + 1); /* { dg-warning "warning: integer overflow in expression" } */ |
| /* { dg-error "error: overflow in constant expression" "constant" { target *-*-* } 33 } */ |
| }; |
| |
| void |
| f (void) |
| { |
| /* This expression is not required to be a constant expression, so |
| it should just involve undefined behavior at runtime. */ |
| int c = INT_MAX + 1; /* { dg-warning "warning: integer overflow in expression" } */ |
| /* { dg-bogus "error: overflow in constant expression" "constant" { xfail *-*-* } 42 } */ |
| } |
| |
| /* But this expression does need to be constant. */ |
| static int sc = INT_MAX + 1; /* { dg-warning "warning: integer overflow in expression" } */ |
| /* { dg-error "error: overflow in constant expression" "constant" { target *-*-* } 47 } */ |
| |
| /* The first two of these involve overflow, so are not null pointer |
| constants. The third has the overflow in an unevaluated |
| subexpression, so is a null pointer constant. */ |
| void *p = 0 * (INT_MAX + 1); /* { dg-warning "warning: integer overflow in expression" } */ |
| /* { dg-error "error: overflow in constant expression" "constant" { target *-*-* } 53 } */ |
| /* { dg-error "error: initialization makes pointer from integer without a cast" "null" { target *-*-* } 53 } */ |
| void *q = 0 * (1 / 0); /* { dg-warning "warning: division by zero" } */ |
| /* { dg-error "error: initialization makes pointer from integer without a cast" "null" { xfail *-*-* } 56 } */ |
| void *r = (1 ? 0 : INT_MAX+1); |
| |
| void |
| g (int i) |
| { |
| switch (i) |
| { |
| case 0 * (1/0): /* { dg-warning "warning: division by zero" } */ |
| ; |
| case 1 + 0 * (INT_MAX + 1): /* { dg-warning "warning: integer overflow in expression" } */ |
| /* { dg-error "error: overflow in constant expression" "constant" { target *-*-* } 67 } */ |
| ; |
| } |
| } |
| |
| int |
| h (void) |
| { |
| return INT_MAX + 1; /* { dg-warning "warning: integer overflow in expression" } */ |
| } |
| |
| int |
| h1 (void) |
| { |
| return INT_MAX + 1 - INT_MAX; /* { dg-warning "warning: integer overflow in expression" } */ |
| } |
| |
| void fuc (unsigned char); |
| void fsc (signed char); |
| |
| void |
| h2 (void) |
| { |
| fsc (SCHAR_MAX + 1); /* { dg-warning "warning: overflow in implicit constant conversion" } */ |
| fsc (SCHAR_MIN - 1); /* { dg-warning "warning: overflow in implicit constant conversion" } */ |
| fsc (UCHAR_MAX); /* { dg-warning "warning: overflow in implicit constant conversion" } */ |
| fsc (UCHAR_MAX + 1); /* { dg-warning "warning: overflow in implicit constant conversion" } */ |
| fuc (-1); |
| fuc (UCHAR_MAX + 1); /* { dg-warning "warning: large integer implicitly truncated to unsigned type" } */ |
| fuc (SCHAR_MIN); |
| fuc (SCHAR_MIN - 1); /* { dg-warning "warning: large integer implicitly truncated to unsigned type" } */ |
| fuc (-UCHAR_MAX); /* { dg-warning "warning: large integer implicitly truncated to unsigned type" } */ |
| } |
| |
| void fui (unsigned int); |
| void fsi (signed int); |
| |
| int si; |
| unsigned ui; |
| |
| void |
| h2i (int x) |
| { |
| /* For some reason, we only give certain warnings for implicit |
| conversions among values of the same precision with -Wconversion, |
| while we don't give others at all. */ |
| fsi ((unsigned)INT_MAX + 1); |
| si = (unsigned)INT_MAX + 1; |
| si = x ? (unsigned)INT_MAX + 1 : 1; |
| fsi ((unsigned)INT_MAX + 2); |
| si = (unsigned)INT_MAX + 2; |
| si = x ? (unsigned)INT_MAX + 2 : 1; |
| fsi (UINT_MAX); |
| si = UINT_MAX; |
| fui (-1); |
| ui = -1; |
| ui = x ? -1 : 1U; |
| fui (INT_MIN); |
| ui = INT_MIN; |
| ui = x ? INT_MIN : 1U; |
| } |