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/* $NetBSD: msg_161.c,v 1.11 2023/06/19 12:33:43 rillig Exp $ */
# 3 "msg_161.c"
// Test for message: constant in conditional context [161]
/* lint1-extra-flags: -h -X 351 */
void
while_1(void)
{
/* expect+1: warning: constant in conditional context [161] */
while (1)
continue;
}
void
while_0(void)
{
/* expect+1: warning: constant in conditional context [161] */
while (0) {
/* expect+1: warning: statement not reached [193] */
continue;
}
}
/*
* The pattern 'do { } while (0)' is a common technique to define a
* preprocessor macro that behaves like a single statement. There is
* nothing unusual or surprising about the constant condition.
* Before tree.c 1.202 from 2021-01-31, lint warned about it.
*/
void
do_while_0(void)
{
do {
} while (0);
}
void
do_while_1(void)
{
do {
/* expect+1: warning: constant in conditional context [161] */
} while (1);
}
extern void println(const char *);
/*
* Since 2021-02-28, lint no longer warns about constant controlling
* expressions involving sizeof since these are completely legitimate.
*/
void
test_sizeof(void)
{
if (sizeof(int) > sizeof(char))
println("very probable");
if (sizeof(int) < sizeof(char))
println("impossible");
}
const _Bool conditions[] = {
/* XXX: Why no warning here? */
13 < 13,
/* XXX: Why no warning here? */
0 < 0,
/* XXX: Why no warning here? */
0 != 0,
/* expect+1: warning: constant in conditional context [161] */
0 == 0 && 1 == 0,
/* expect+1: warning: constant in conditional context [161] */
1 == 0 || 2 == 1,
/* expect+2: warning: constant in conditional context [161] */
/* expect+1: error: non-constant initializer [177] */
0 == 0 && ""[0] == '\0',
/* expect+2: warning: constant in conditional context [161] */
/* expect+1: error: non-constant initializer [177] */
""[0] == '\0' && 0 == 0,
/* C99 6.6p3: Constant expressions shall not contain [...] comma */
/* expect+2: warning: expression has null effect [129] */
/* expect+1: error: non-constant initializer [177] */
(0 == 0, 1 == 0),
};
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