[Mesa-dev] [PATCH 1/3] util: Fix SHA1 implementation on big endian

[Andres Gomez]

On Fri, 2017-11-24 at 13:32 +0000, Emil Velikov wrote:
> On 24 November 2017 at 10:25, Eric Engestrom <eric.engestrom at imgtec.com> wrote:
> > On Thursday, 2017-11-23 11:08:04 -0800, Matt Turner wrote:
> > > The code defines a macro blk0(i) based on the preprocessor condition
> > > BYTE_ORDER == LITTLE_ENDIAN. If true, blk0(i) is defined as a byte swap
> > > operation. Unfortunately, if the preprocessor macros used in the test
> > > are no defined, then the comparison becomes 0 == 0 and it evaluates as
> > > true.
> > > ---
> > >  src/util/sha1/sha1.c | 9 +++++++++
> > >  1 file changed, 9 insertions(+)
> > > 
> > > diff --git a/src/util/sha1/sha1.c b/src/util/sha1/sha1.c
> > > index ef59ea1dfc..2c629520c3 100644
> > > --- a/src/util/sha1/sha1.c
> > > +++ b/src/util/sha1/sha1.c
> > > @@ -16,8 +16,17 @@
> > > 
> > >  #include <stdint.h>
> > >  #include <string.h>
> > > +#include "u_endian.h"
> > 
> > If you're including this header, why not use
> > `#ifdef PIPE_ARCH_LITTLE_ENDIAN` instead of
> > `#if BYTE_ORDER == LITTLE_ENDIAN`?
> > 
> > `#error` becomes unnecessary
> > 
> 
> I won't bother with that - we do want to address all the cases where
> undefined macro is used in #if statement.
> This is handled by -Wundef which seemingly is not part of Wall and we
> don't use - patch incoming in a second.
> 
> We want to make it a Werror=undef after we fix the ~60 issues. More
> than half of those are coming from gtest :-\
> 
> Thanks for fixing these Matt. As-is the series is
> Reviewed-by: Emil Velikov <emil.velikov at collabora.com>

Matt, this is breaking Windows compilation.

You can check the Appveyor output here:
https://ci.appveyor.com/project/AndresGomez/mesa-dwep2/build/488

I've also seen a similar error with the MinGW crosscompilation to
Windows:

--

src/util/hash_table.c: In function ‘_mesa_hash_table_u64_insert’:
src/util/hash_table.c:591:42: warning: cast to pointer from integer of
different size [-Wint-to-pointer-cast]
       _mesa_hash_table_insert(ht->table, (void *)key, data);
                                          ^
src/util/hash_table.c: In function ‘hash_table_u64_search’:
src/util/hash_table.c:607:49: warning: cast to pointer from integer of
different size [-Wint-to-pointer-cast]
       return _mesa_hash_table_search(ht->table, (void *)key);
                                                 ^
src/util/sha1/sha1.c:23:2: error: #error BYTE_ORDER not defined
 #error BYTE_ORDER not defined
  ^
src/util/sha1/sha1.c:27:2: error: #error LITTLE_ENDIAN no defined
 #error LITTLE_ENDIAN no defined
  ^
scons: *** [build/windows-x86-debug/util/sha1/sha1.o] Error 1
scons: building terminated because of errors.

-- 
Br,

Andres