On 2016-05-02 05:18 PM, Amaury Pouly via rockbox-dev wrote:
Hi fellow developers,
I noticed that the ARM toolchain compilation is broken with newer GCCs.
So I intend to push this patch:
http://gerrit.rockbox.org/r/#/c/1297/
that comes together with this:
http://rockbox.org/gcc/gcc-c11-toplev.diff
I am confident the patch is good because it does not come from me ;)
That being said, it would be nice if some of could double-check if you
can build the ARM toolchain with this new patch and report the result
(along with your system GCC version). My system gcc is 5.3.1
Using GCC 5.3.1-14ubuntu2 on Ubuntu 16.04 x86_64 I confirm rockboxdev.sh
without the patch runs into errors:
../../gcc-4.4.4/gcc/toplev.c: At top level:
../../gcc-4.4.4/gcc/toplev.c:536:1: error: redefinition of ‘floor_log2’
floor_log2 (unsigned HOST_WIDE_INT x)
^
In file included from ../../gcc-4.4.4/gcc/toplev.c:58:0:
../../gcc-4.4.4/gcc/toplev.h:190:1: note: previous definition of ‘floor_log2’
was here
floor_log2 (unsigned HOST_WIDE_INT x)
^
../../gcc-4.4.4/gcc/toplev.c:571:1: error: redefinition of ‘exact_log2’
exact_log2 (unsigned HOST_WIDE_INT x)
^
In file included from ../../gcc-4.4.4/gcc/toplev.c:58:0:
../../gcc-4.4.4/gcc/toplev.h:196:1: note: previous definition of ‘exact_log2’
was here
exact_log2 (unsigned HOST_WIDE_INT x)
Compilation with the patch works. After getting the errors and adding
the patch I first got link time errors, but it worked after a "make clean".
The removal of #ifdef CLZ_HWI and #ifdef CTZ_HWI code is not needed for
successful building. That changes floor_log2() and exact_log2() from
code based on one of the __builtin_clz functions to alternative code.
I'm left wondering what is the reason for that change.
My old compiler, a new one with this patch, and a new one without the
#ifdef code removal all produce the exact same ipodvideo rockbox.bin.
Best regards,
Boris
