Returning a negative value for a boolean function seem to have the
undesired effect of returning true. require_paranoia_below() is a
boolean function, but the variable used to store the return value is an
integer, receiving -1 or 0. This patch convert rc to bool, replace -1
by false, and 0 by true.
This issue was found by the following Coccinelle semantic patch:
<smpl>
@@
identifier f, ret;
constant C;
typedef bool;
@@
bool f (...){
<+...
ret = -C;
...
* return ret;
...+>
}
</smpl>
Signed-off-by: Peter Senna Tschudin <[email protected]>
---
I could not compile this specific file, but I did some testing on toy examples:
t.c:
_Bool main(void)
{
return -1;
}
$ powerpc64-linux-gnu-gcc -O2 -S -fomit-frame-pointer t.c
t.s:
...
.L.main:
li 3,1
blr
However if the function type is int instead of bool, it behaves as
expected:
t2.c:
int main(void)
{
return -1;
}
$ powerpc64-linux-gnu-gcc -O2 -S -fomit-frame-pointer t2.c
t2.s:
...
.L.main:
li 3,-1
blr
So another solution would be to change the function type to int.
tools/testing/selftests/powerpc/pmu/lib.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/powerpc/pmu/lib.c
b/tools/testing/selftests/powerpc/pmu/lib.c
index a07104c..2f17110 100644
--- a/tools/testing/selftests/powerpc/pmu/lib.c
+++ b/tools/testing/selftests/powerpc/pmu/lib.c
@@ -219,9 +219,9 @@ bool require_paranoia_below(int level)
unsigned long current;
char *end, buf[16];
FILE *f;
- int rc;
+ bool rc;
- rc = -1;
+ rc = false;
f = fopen(PARANOID_PATH, "r");
if (!f) {
@@ -244,7 +244,7 @@ bool require_paranoia_below(int level)
if (current >= level)
goto out;
- rc = 0;
+ rc = true;
out_close:
fclose(f);
out:
--
2.1.0
--
To unsubscribe from this list: send the line "unsubscribe linux-api" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
