[PATCH] lib: Fix bug in int_sqrt() for 64 bit longs

The implementation of int_sqrt() assumes that longs have 32 bits. On systems that have 64 bit longs this will result in gross errors when the argument to the function is greater than 2^32 - 1 on such systems. I doubt whether any such use is currently made of int_sqrt() but the attached patch fixes the problem anyway.

Signed-off-by: Peter Williams <[email protected]>

--
Peter Williams                                   [email protected]

"Learning, n. The kind of ignorance distinguishing the studious."
 -- Ambrose Bierce

Index: GIT-warnings/lib/int_sqrt.c
===================================================================
--- GIT-warnings.orig/lib/int_sqrt.c	2005-10-25 13:55:22.000000000 +1000
+++ GIT-warnings/lib/int_sqrt.c	2006-01-06 14:29:19.000000000 +1100
@@ -15,7 +15,7 @@ unsigned long int_sqrt(unsigned long x)
 	op = x;
 	res = 0;
 
-	one = 1 << 30;
+	one = 1 << (BITS_PER_LONG - 2);
 	while (one > op)
 		one >>= 2;
 

---

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