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void test_direct (void)
{
test_direct (); /* { dg-warning "infinite recursion" } */
}
void test_guarded (int flag)
{
if (flag)
test_guarded (flag); /* { dg-warning "infinite recursion" } */
}
void test_flipped_guard (int flag)
{
if (flag)
test_guarded (!flag); /* { dg-bogus "infinite recursion" } */
}
void test_param_variant (int depth)
{
if (depth > 0)
test_param_variant (depth - 1); /* { dg-bogus "infinite recursion" } */
}
void test_unguarded_param_variant (int depth)
{
/* We fail to report this: we see that depth is being decremented,
but don't notice that every path through the function is
recursing. */
test_unguarded_param_variant (depth - 1); /* { dg-warning "infinite recursion" "TODO" { xfail *-*-* } } */
}
int g;
void test_global_variant ()
{
if (g-- > 0)
test_global_variant (); /* { dg-bogus "infinite recursion" } */
}
/* This is a bounded recursion, as "n" is decremented before recursing... */
int test_while_do_predecrement_param (int n)
{
int x = 0;
while (n)
x += test_while_do_predecrement_param (--n); /* { dg-bogus "infinite recursion" } */
return x;
}
/* ...whereas this one is unbounded, as "n" is decremented *after* the
recursive call, and so is repeatedly called with the same value. */
int test_while_do_postdecrement_param (int n)
{
int x = 0;
while (n)
x += test_while_do_postdecrement_param (n--); /* { dg-warning "infinite recursion" } */
return x;
}
/* This is a bounded recursion, as "n" is decremented before recursing... */
int test_do_while_predecrement_param (int n)
{
int x = 0;
do
x += test_do_while_predecrement_param (--n); /* { dg-bogus "infinite recursion" } */
while (--n);
return x;
}
/* ...whereas this one is unbounded, as "n" is decremented *after* the
recursive call, and so is repeatedly called with the same value. */
int test_do_while_postdecrement_param (int n)
{
int x = 0;
do
x += test_do_while_postdecrement_param (n--); /* { dg-warning "infinite recursion" } */
while (--n);
return x;
}
/* Various cases of decrementing "n" as the recursion proceeds where
not every path recurses, but we're not actually checking "n", so
if "flag" is true it's an infinite recursion. */
void test_partially_guarded_postdecrement (int flag, int n)
{
/* We catch this; the "n--" means we recurse with the
same value for the 2nd param. */
if (flag) /* { dg-message "when 'flag != 0'" } */
test_partially_guarded_postdecrement (flag, n--); /* { dg-warning "infinite recursion" } */
}
void test_partially_guarded_predecrement (int flag, int n)
{
/* We fail to report this; we see that "n" is changing,
though it isn't relevant to whether we recurse. */
if (flag)
test_partially_guarded_predecrement (flag, --n); /* { dg-warning "infinite recursion" "TODO" { xfail *-*-* } } */
}
void test_partially_guarded_subtract (int flag, int n)
{
/* We fail to report this; we see that "n" is changing,
though it isn't relevant to whether we recurse. */
if (flag)
test_partially_guarded_subtract (flag, n - 1); /* { dg-warning "infinite recursion" "TODO" { xfail *-*-* } } */
}
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