tags 984057 + patch user debian-rele...@lists.debian.org usertags 984057 + bsp-2022-10-de-karlsruhe thank you
Matthias Klose wrote...
> /<<PKGBUILDDIR>>/include/linux-x86_64/sysdep.h:109:5: error: array subscript
> ‘struct xchg_dummy[0]’ is partly outside array bounds of ‘psmi_spinlock_t[1]’
> {aka ‘ips_atomic_t[1]’} [-Werror=array-bounds]
> 109 | asm volatile(LOCK_PREFIX "cmpxchgl %1,%2"
> | ^~~
After staring at this for a while I think upstream did some creepy
things gcc is understandably happy, but overall this code in sysdep.h
| static __inline__ uint32_t ips_cmpxchg(volatile uint32_t *ptr,
| uint32_t old, uint32_t new)
| {
| uint32_t prev;
| struct xchg_dummy { uint32_t a[100]; };
|
| asm volatile(LOCK_PREFIX "cmpxchgl %1,%2"
| : "=a"(prev)
| : "q"(new), "m"(*(struct xchg_dummy *)ptr), "0"(old)
| : "memory");
|
| return prev;
| }
is okay-ish. And so, unless someone finds a saner way (I guess it's
replacing the 100 with a better value, possibly architecture-dependent),
I'd just disable the warning, patch attached, makes the build pass.
Christoph
--- a/include/linux-i386/sysdep.h
+++ b/include/linux-i386/sysdep.h
@@ -106,10 +106,13 @@
uint32_t prev;
struct xchg_dummy { uint32_t a[100]; };
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Warray-bounds"
asm volatile(LOCK_PREFIX "cmpxchgl %1,%2"
: "=a"(prev)
: "q"(new), "m"(*(struct xchg_dummy *)ptr), "0"(old)
: "memory");
+#pragma GCC diagnostic pop
return prev;
}
signature.asc
Description: PGP signature
