/*
* C99 added support for type-generic macros, but these were limited to the
* header <tgmath.h>. C11 made this feature generally available.
*
* The generic selection is typically used with macros, but since lint1 works
* on the preprocessed source, the test cases look a bit strange.
*
* C11 6.5.1.1 "Generic selection"
*/
/* lint1-extra-flags: -Ac11 */
/*
* The type of 'var' is not compatible with any of the types from the
* generic-association. This is a constraint violation that the compiler must
* detect, therefore lint doesn't repeat that diagnostic.
*/
const char *
classify_type_without_default(double var)
{
/* expect-2: warning: parameter 'var' unused in function 'classify_type_without_default' [231] */
return _Generic(var,
long double: "long double",
long long: "long long",
unsigned: "unsigned"
);
/* expect-1: error: function 'classify_type_without_default' expects to return value [214] */
}
/*
* In this case, the 'default' expression is selected.
*/
const char *
classify_type_with_default(double var)
{
/* expect-2: warning: parameter 'var' unused in function 'classify_type_with_default' [231] */
return _Generic(var,
long double: "long double",
long long: "long long",
unsigned: "unsigned",
default: "unknown"
);
}
/*
* The type of a _Generic expression is the one from the selected association.
*/
const char *
classify_char(char c)
{
/* expect-2: warning: parameter 'c' unused in function 'classify_char' [231] */
return _Generic(c,
char: "yes",
default: 0.0
);
}
/*
* Before cgram.y 1.238 from 2021-06-27, lint accepted a comma-expression,
* which looked as if _Generic would accept multiple arguments before the
* selection.
*/
/* ARGSUSED */
const int *
comma_expression(char first, double second)
{
/* expect+1: error: syntax error 'second' [249] */
return _Generic(first, second,
char: "first",
double: 2.0
);
/* expect+1: warning: function 'comma_expression' falls off bottom without returning value [217] */
}
/*
* Ensure that assignment-expressions are accepted by the grammar, as
* opposed to comma-expressions.
*/
/* ARGSUSED */
int
assignment_expression(int first, int second)
{
return _Generic(first = second,
int: second = first
);
}
int
primary_expression(void)
{
return _Generic(0, int: assignment_expression)(0, 0);
}
/*
* The types don't match, therefore build_generic_selection returns NULL,
* which is then silently ignored by init_expr. This situation is already
* covered by the compilers, so there is no need for lint to double-check it.
*/
const char *x = _Generic(
1ULL + 1.0f,
int: 1
);
