[2.4] gcc3 warns about type-punned pointers ?

[J.A. Magallon]

Hi all...

gcc3 gives this warning when using the __set_64bit_var function:

/usr/src/linux/include/asm/system.h:190: warning: dereferencing type-punned pointer will break strict-aliasing rules

Is it a potential problem ?

This seems to cure it:

--- linux-2.4.22-jam1m/include/asm-i386/system.h.orig	2003-08-29 00:26:41.000000000 +0200
+++ linux-2.4.22-jam1m/include/asm-i386/system.h	2003-08-29 00:26:55.000000000 +0200
@@ -181,8 +181,8 @@
 {
 	__set_64bit(ptr,(unsigned int)(value), (unsigned int)((value)>>32ULL));
 }
-#define ll_low(x)	*(((unsigned int*)&(x))+0)
-#define ll_high(x)	*(((unsigned int*)&(x))+1)
+#define ll_low(x)	*(((unsigned int*)(void*)&(x))+0)
+#define ll_high(x)	*(((unsigned int*)(void*)&(x))+1)
 
 static inline void __set_64bit_var (unsigned long long *ptr,
 			 unsigned long long value)

A collateral question: why is the reason for this function ?
long long assignments are not atomic in gcc ?

TIA

-- 
J.A. Magallon <jamagallon@xxxxxxx>      \                 Software is like sex:
werewolf.able.es                         \           It's better when it's free
Mandrake Linux release 9.2 (Cooker) for i586
Linux 2.4.22-jam1m (gcc 3.3.1 (Mandrake Linux 9.2 3.3.1-1mdk))
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