When compiling for i386-softmmu under MSYS2, GCC emits the following warning:
In function 'get_reg_val',
inlined from 'calc_modrm_operand64' at
../src/target/i386/emulate/x86_decode.c:1796:15:
../src/target/i386/emulate/x86_decode.c:1703:5: error: 'memcpy' forming
offset [4, 7] is out of the bounds [0, 4] of object 'val' with type
'target_ulong' {aka 'unsigned int'} [-Werror=array-bounds=]
1703 | memcpy(&val,
| ^~~~~~~~~~~~
1704 | get_reg_ref(env, reg, rex_present, is_extended, size),
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1705 | size);
| ~~~~~
../src/target/i386/emulate/x86_decode.c: In function 'calc_modrm_operand64':
../src/target/i386/emulate/x86_decode.c:1702:18: note: 'val' declared here
1702 | target_ulong val = 0;
| ^~~
In the calc_modrm_operand64() case the compiler sees size == 8 to be mem-copied
to a target_ulong variable which is only 4 bytes wide in case of i386-softmmu.
Note that when size != 1, get_reg_ref() always returns a pointer to an 8 byte
register, regardless of the target_ulong size. Fix the compiler warning by
always providing 8 bytes of storage by means of uint64_t.
Fixes: 77a2dba45cc9 ("target/i386/emulate: stop overloading decode->op[N].ptr")
cc: qemu-stable
Signed-off-by: Bernhard Beschow <[email protected]>
---
target/i386/emulate/x86_decode.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/target/i386/emulate/x86_decode.c b/target/i386/emulate/x86_decode.c
index d037ed1142..6ad03b71b0 100644
--- a/target/i386/emulate/x86_decode.c
+++ b/target/i386/emulate/x86_decode.c
@@ -1699,7 +1699,7 @@ void *get_reg_ref(CPUX86State *env, int reg, int
rex_present,
target_ulong get_reg_val(CPUX86State *env, int reg, int rex_present,
int is_extended, int size)
{
- target_ulong val = 0;
+ uint64_t val = 0;
memcpy(&val,
get_reg_ref(env, reg, rex_present, is_extended, size),
size);
--
2.53.0
