I've built linux-2.6.24 for arm using gcc-4.3.1 and while it builds fine, the
resulting binary doesn't boot on qemu. If I build the same kernel with
gcc-4.2.4 it boots correctly.
The problem seems to be that the prefetch function
(linux-2.6.24/include/asm-arm/processor.h) causes a crash if it is called with
a NULL pointer argument. But only if it's compiled with gcc-4.3.x.
This patch fixes the problem, but the extra code may cost more than you gain by
having prefetch in the first place
diff -urN linux-2.6.24-clean/include/asm-arm/processor.h
linux-2.6.24/include/asm-arm/processor.h
--- linux-2.6.24-clean/include/asm-arm/processor.h 2008-01-24
22:58:37.000000000 +0000
+++ linux-2.6.24/include/asm-arm/processor.h 2008-07-02 22:44:26.052525328
+0100
@@ -105,11 +105,14 @@
#define ARCH_HAS_PREFETCH
static inline void prefetch(const void *ptr)
{
- __asm__ __volatile__(
- "pld\t%0"
- :
- : "o" (*(char *)ptr)
- : "cc");
+ if (ptr)
+ {
+ __asm__ __volatile__(
+ "pld\t%0"
+ :
+ : "o" (*(char *)ptr)
+ : "cc");
+ }
}
#define ARCH_HAS_PREFETCHW
--
Summary: [Regression] linux-kernel 2.6.24 doesn't boot for arm
Product: gcc
Version: 4.3.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: chris dot steel dot lnx at googlemail dot com
GCC build triplet: x86_64-cross-linux-gnu
GCC host triplet: x86_64-cross-linux-gnu
GCC target triplet: arm-unknown-linux-gnueabi
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36706
