[Buildroot] [git commit] assimp: work around gcc bug on SuperH

[Buildroot] [git commit] assimp: work around gcc bug on SuperH

[Thomas Petazzoni]

commit: https://git.buildroot.net/buildroot/commit/?id=68cebedeb977396f64f5f591f5e93f34fab8e0a8
branch: https://git.buildroot.net/buildroot/commit/?id=refs/heads/master

gcc versions earlier than gcc 6.x fail to build assimp on SuperH when
static linking:

  AssxmlExporter.cpp:623:1: error: unable to find a register to spill in class 'GENERAL_REGS'

It's the combination of -Os and *not* having -fPIC that makes gcc
fail, which explains why configurations with dynamic linking work
fine.

 -Os -fPIC -> works
 -Os       -> fails
 -O2 -fPIC -> works
 -O2       -> works

Therefore, as a workaround, we are forcing the use of -O2 on SuperH
when the gcc version is older than gcc 6.x and we're statically
linking.

Fixes:

  http://autobuild.buildroot.net/results/ec88aa8118179e30e24603cc45292047dca19216/

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
 package/assimp/assimp.mk | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/package/assimp/assimp.mk b/package/assimp/assimp.mk
index 08893ff..298e121 100644
--- a/package/assimp/assimp.mk
+++ b/package/assimp/assimp.mk
@@ -16,6 +16,14 @@ ifeq ($(BR2_m68k),y)
 ASSIMP_CXXFLAGS += -mxgot
 endif
 
+# workaround SuperH compiler failure when static linking (i.e -fPIC is
+# not passed) in gcc versions 5.x or older. The -Os optimization level
+# causes a "unable to find a register to spill in class
+# ???GENERAL_REGS???" error. -O2 works fine.
+ifeq ($(BR2_sh):$(BR2_STATIC_LIBS):$(BR2_HOST_GCC_AT_LEAST_6),y:y:)
+ASSIMP_CXXFLAGS += -O2
+endif
+
 ASSIMP_CONF_OPTS += -DASSIMP_BUILD_TESTS=OFF \
 	-DCMAKE_CXX_FLAGS="$(TARGET_CXXFLAGS) $(ASSIMP_CXXFLAGS)"
 

[Buildroot] [git commit] assimp: work around gcc bug on SuperH

[Peter Korsgaard]

>>>>> "Thomas" == Thomas Petazzoni <thomas.petazzoni@free-electrons.com> writes:

 > commit: https://git.buildroot.net/buildroot/commit/?id=68cebedeb977396f64f5f591f5e93f34fab8e0a8
 > branch: https://git.buildroot.net/buildroot/commit/?id=refs/heads/master

 > gcc versions earlier than gcc 6.x fail to build assimp on SuperH when
 > static linking:

 >   AssxmlExporter.cpp:623:1: error: unable to find a register to spill in class 'GENERAL_REGS'

 > It's the combination of -Os and *not* having -fPIC that makes gcc
 > fail, which explains why configurations with dynamic linking work
 > fine.

 >  -Os -fPIC -> works
 >  -Os       -> fails
 >  -O2 -fPIC -> works
 >  -O2       -> works

 > Therefore, as a workaround, we are forcing the use of -O2 on SuperH
 > when the gcc version is older than gcc 6.x and we're statically
 > linking.

 > Fixes:

 >   http://autobuild.buildroot.net/results/ec88aa8118179e30e24603cc45292047dca19216/

 > Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
 > ---
 >  package/assimp/assimp.mk | 8 ++++++++
 >  1 file changed, 8 insertions(+)

 > diff --git a/package/assimp/assimp.mk b/package/assimp/assimp.mk
 > index 08893ff..298e121 100644
 > --- a/package/assimp/assimp.mk
 > +++ b/package/assimp/assimp.mk
 > @@ -16,6 +16,14 @@ ifeq ($(BR2_m68k),y)
 >  ASSIMP_CXXFLAGS += -mxgot
 >  endif
 
 > +# workaround SuperH compiler failure when static linking (i.e -fPIC is
 > +# not passed) in gcc versions 5.x or older. The -Os optimization level
 > +# causes a "unable to find a register to spill in class
 > +# ??GENERAL_REGS??" error. -O2 works fine.

Any specific reason for the unicode quotes?

> +ifeq ($(BR2_sh):$(BR2_STATIC_LIBS):$(BR2_HOST_GCC_AT_LEAST_6),y:y:)

HOST_GCC? Don't you mean BR2_TOOLCHAIN_GCC_AT_LEAST_6?

-- 
Bye, Peter Korsgaard

[Buildroot] [git commit] assimp: work around gcc bug on SuperH

[Thomas Petazzoni]

Hello,

On Mon, 27 Feb 2017 22:00:03 +0100, Peter Korsgaard wrote:

>  > +# workaround SuperH compiler failure when static linking (i.e -fPIC is
>  > +# not passed) in gcc versions 5.x or older. The -Os optimization level
>  > +# causes a "unable to find a register to spill in class
>  > +# __GENERAL_REGS__" error. -O2 works fine.  
> 
> Any specific reason for the unicode quotes?

Nope, this message was copy/pasted from the gcc output, so the quotes
come from here.

> > +ifeq ($(BR2_sh):$(BR2_STATIC_LIBS):$(BR2_HOST_GCC_AT_LEAST_6),y:y:)  
> 
> HOST_GCC? Don't you mean BR2_TOOLCHAIN_GCC_AT_LEAST_6?

Gaah. Shit. I'll fix this. Thanks for reviewing.

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com