[PATCH 1/2] lib/lcm.c: Ensure correct result whenever it fits
From: Rasmus Villemoes
Date: Tue Dec 09 2014 - 16:03:33 EST
Ensure that lcm(a,b) returns the mathematically correct result,
provided it fits in an unsigned long. The current version returns
garbage if a*b overflows, even if the final result would fit.
Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
---
lib/lcm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/lcm.c b/lib/lcm.c
index b9c8de461e9e..01b3aa922dda 100644
--- a/lib/lcm.c
+++ b/lib/lcm.c
@@ -7,7 +7,7 @@
unsigned long lcm(unsigned long a, unsigned long b)
{
if (a && b)
- return (a * b) / gcd(a, b);
+ return (a / gcd(a, b)) * b;
else if (b)
return b;
--
2.1.3
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