diff options
| author | Mathias Krause <minipli@googlemail.com> | 2012-07-17 20:52:17 +0200 |
|---|---|---|
| committer | Stefan Reinauer <stefan.reinauer@coreboot.org> | 2012-07-18 00:15:15 +0200 |
| commit | d2567c8d92cb2c816dc9e8078740aad93d14dc32 (patch) | |
| tree | 6ea2f14dea5230af9d7199acb0ec261c74efc27c | |
| parent | 117198662778778d132ee6077c1f39635adbadd9 (diff) | |
| download | coreboot-d2567c8d92cb2c816dc9e8078740aad93d14dc32.tar.xz | |
cbfstool: make endian detection code more robust
Accessing the memory of a char array through a uint32_t pointer breaks
strict-aliasing rules as it dereferences memory with lower alignment
requirements than the type of the pointer requires. It's no problem on
x86 as the architecture is able to handle unaligned memory access but
other architectures are not.
Fix this by doing the test the other way around -- accessing the first
byte of a uint32_t variable though a uint8_t pointer.
Change-Id: Id340b406597014232741c98a4fd0b7c159f164c2
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Reviewed-on: http://review.coreboot.org/1234
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: build bot (Jenkins)
| -rw-r--r-- | util/cbfstool/cbfstool.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/util/cbfstool/cbfstool.c b/util/cbfstool/cbfstool.c index 9dbdc1c11a..721bf33fa2 100644 --- a/util/cbfstool/cbfstool.c +++ b/util/cbfstool/cbfstool.c @@ -339,9 +339,9 @@ int host_bigendian = 0; static void which_endian(void) { - char test[4] = "1234"; - uint32_t inttest = *(uint32_t *) test; - if (inttest == 0x31323334) { + static const uint32_t inttest = 0x12345678; + uint8_t inttest_lsb = *(uint8_t *)&inttest; + if (inttest_lsb == 0x12) { host_bigendian = 1; } } |