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/* { dg-additional-options "-O0" } */
extern int maybe_useful_work ();
int global_var;
volatile int volatile_global_var;
struct st
{
int x;
int y;
};
static void __attribute__((noinline))
do_nothing (void)
{
}
void test_empty_while_true ()
{
while (1) {} /* { dg-warning "infinite loop" } */
/* { dg-message "looping back\.\.\." "" { target *-*-* } .-1 } */
/* { dg-message "\.\.\.to here" "" { target *-*-* } .-2 } */
}
void test_empty_do_while ()
{
do {} while (1); /* { dg-warning "infinite loop" } */
/* { dg-message "looping back\.\.\." "" { target *-*-* } .-1 } */
/* { dg-message "\.\.\.to here" "" { target *-*-* } .-2 } */
}
void test_empty_for ()
{
for (;;) {} /* { dg-warning "infinite loop" } */
/* { dg-message "looping back\.\.\." "" { target *-*-* } .-1 } */
/* { dg-message "\.\.\.to here" "" { target *-*-* } .-2 } */
}
void test_while_true_maybe_useful_work ()
{
while (1)
maybe_useful_work ();
}
void test_while_true_interproc_empty ()
{
/* Depending on optimization level, location is sometimes
on "while", sometimes on "do_nothing", and sometimes the
unknown location. */
while (1)
do_nothing (); /* { dg-warning "infinite loop" } */
}
void test_while_true_increment_local ()
{
int i = 0;
while (1)
i++; /* { dg-warning "infinite loop" } */
}
void test_while_true_increment_global ()
{
while (1)
global_var++;
}
void test_guarded_while_true_increment_local (int flag)
{
if (flag)
{
int i = 0;
while (1)
i++; /* { dg-warning "infinite loop" } */
}
}
void test_while_local_flag_increment_local (int flag)
{
int i = 0;
while (flag) /* { dg-warning "infinite loop" } */
i++;
}
extern int check_flag (void);
void test_while_calling_fn (void)
{
while (check_flag ())
do_nothing ();
}
void test_missing_parens_on_call (void)
{
while (check_flag)
do_nothing (); /* { dg-warning "infinite loop" } */
}
void test_iteration_copy_and_paste_error (int m, int n)
{
/* Wrong variable is incremented in inner "for" loop, thus
effectively an infinite loop. */
float arr[m][n];
for (int i = 0; i < m; i++)
for (int j = 0; j < n; i++) /* { dg-warning "infinite loop" } */
arr[i][j] = 0.f;
}
void test_missing_comparison_in_for_condition_1 (int n)
{
/* Should have been "i < n", rather than just "n". */
for (int i = 0; n; i++) /* { dg-warning "infinite loop" } */
{
}
}
int test_missing_comparison_in_for_condition_2 (int val, int *arr, int n)
{
/* Should have been "i < n", rather than just "n". */
int acc = 0;
for (int i = 0; n; i++) /* { dg-warning "infinite loop" } */
acc += arr[i];
return acc;
}
void test_non_volatile_local_1 (void)
{
int flag = 0;
while (!flag) /* { dg-warning "infinite loop" } */
{
}
}
void test_non_volatile_local_2a (void)
{
int flag = 0;
/* Perhaps should complain about this.
Although the infinite loop might be doing useful work,
"while (!flag)" is a misleading way to spell "infinite loop". */
while (!flag)
maybe_useful_work ();
}
void test_non_volatile_local_2b (void)
{
int flag = 0;
while (!flag)
flag = maybe_useful_work ();
}
void test_non_volatile_local_3a (int n)
{
int i = 0;
/* Perhaps should complain about this.
Although the infinite loop might be doing useful work,
"while (i < n)" is a misleading way to spell "infinite loop". */
while (i < n)
maybe_useful_work ();
}
void test_non_volatile_local_3b (int n)
{
int i = 0;
while (i < n)
{
maybe_useful_work ();
i++;
}
}
void test_volatile_local (void)
{
volatile int flag = 0;
while (!flag) /* { dg-bogus "infinite loop" } */
{
}
}
void test_non_volatile_global (void)
{
/* Not sure if we should warn here. */
while (!global_var) /* { dg-warning "infinite loop" } */
{
}
}
void test_volatile_global (void)
{
while (!volatile_global_var) /* { dg-bogus "infinite loop" } */
{
}
}
void test_field_1 (struct st *p)
{
/* Not sure if we should warn here. */
while (!p->x) /* { dg-warning "infinite loop" } */
{
}
}
void test_field_2 (struct st *p)
{
while (!p->x) /* { dg-bogus "infinite loop" } */
maybe_useful_work ();
}
int missing_init_of_i (int *arr, unsigned n)
{
int sum = 0;
for (int i; i < n; i--) /* { dg-warning "use of uninitialized value 'i'" } */
sum += arr[i];
return sum;
}
void test_switch (char *pc)
{
while (1)
{
char opcode = *pc; /* { dg-warning "infinite loop" } */
switch (opcode) /* { dg-message "if it ever follows 'default:' branch, it will always do so\.\.\." } */
{
case 'A':
pc++;
break;
case 'B':
return;
}
}
}
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