[Mesa-dev] [PATCH] Android: Fix LLVM duplicated symbols linking for N and M

[Chih-Wei Huang]

2017-08-19 8:27 GMT+08:00 Emil Velikov <emil.l.velikov at gmail.com>:
> On 18 August 2017 at 20:46, Rob Herring <robh at kernel.org> wrote:
>> Both statically linking libLLVMCore and dynamically linking libLLVM causes
>> duplicated symbols in gallium_dri.so and it fails to dlopen. We don't
>> really need to link libLLVMCore, but just need generated headers to be
>> built first. Dynamically linking to libLLVM instead is enough to do
>> that. Thanks to Qiang Yu for finding the root cause.
>>
> Nice find indeed, thanks.
>
> This reminds me - a small task for a rainy day.
> - Wire the version script files into the Android build - see the
> autoconf snippet below.
> It will hide the hundreds of symbols when static linking LLVM (aka
> sidestep the current issue) and make the binary noticeably smaller.
>
> gallium_dri_la_LDFLAGS += \
>        -Wl,--version-script=$(top_srcdir)/src/gallium/targets/dri/dri.sym
>
>> With this change, we can align all versions and just have libLLVM as a
>> shared lib dependency.
>>
>> This also requires changes in the M and N versions of LLVM to export the
>> include paths for libLLVM. AOSP master is okay.
>>
> Perfect :-)
>
>> Fixes: 26aee6f4d5a ("Android: rework LLVM build support")
>> Reported-by: Mauro Rossi <issor.oruam at gmail.com>
>> Cc: Emil Velikov <emil.l.velikov at gmail.com>
>> Cc: 17.2 <mesa-stable at lists.freedesktop.org>
>> Signed-off-by: Qiang Yu <Qiang.Yu at amd.com>
>> Signed-off-by: Rob Herring <robh at kernel.org>
>
> Reviewed-by: Emil Velikov <emil.velikov at collabora.com>
>
>> ---
>>  Android.mk                              | 12 ++++--------
>>  src/amd/Android.common.mk               |  4 +---
>>  src/gallium/drivers/radeon/Android.mk   |  2 +-
>>  src/gallium/drivers/radeonsi/Android.mk |  2 +-
>>  4 files changed, 7 insertions(+), 13 deletions(-)
>>
>> diff --git a/Android.mk b/Android.mk
>> index 6571161c8783..dc4041364551 100644
>> --- a/Android.mk
>> +++ b/Android.mk
>> @@ -92,16 +92,12 @@ define mesa-build-with-llvm
>>    $(if $(filter $(MESA_ANDROID_MAJOR_VERSION), 4 5), \
>>      $(warning Unsupported LLVM version in Android $(MESA_ANDROID_MAJOR_VERSION)),) \
>>    $(if $(filter 6,$(MESA_ANDROID_MAJOR_VERSION)), \
>> -    $(eval LOCAL_CFLAGS += -DHAVE_LLVM=0x0307 -DMESA_LLVM_VERSION_PATCH=0) \
>> -    $(eval LOCAL_STATIC_LIBRARIES += libLLVMCore) \
>> -    $(eval LOCAL_C_INCLUDES += external/llvm/include external/llvm/device/include),) \
>> +    $(eval LOCAL_CFLAGS += -DHAVE_LLVM=0x0307 -DMESA_LLVM_VERSION_PATCH=0),) \

Hmm, why do we need an extra comma?
Does it correspond to the else case of $(if ...)?
If so it could be omitted.

>>    $(if $(filter 7,$(MESA_ANDROID_MAJOR_VERSION)), \
>> -    $(eval LOCAL_CFLAGS += -DHAVE_LLVM=0x0308 -DMESA_LLVM_VERSION_PATCH=0) \
>> -    $(eval LOCAL_STATIC_LIBRARIES += libLLVMCore) \
>> -    $(eval LOCAL_C_INCLUDES += external/llvm/include external/llvm/device/include),) \
>> +    $(eval LOCAL_CFLAGS += -DHAVE_LLVM=0x0308 -DMESA_LLVM_VERSION_PATCH=0),) \
>>    $(if $(filter O,$(MESA_ANDROID_MAJOR_VERSION)), \
>> -    $(eval LOCAL_CFLAGS += -DHAVE_LLVM=0x0309 -DMESA_LLVM_VERSION_PATCH=0) \
>> -    $(eval LOCAL_HEADER_LIBRARIES += llvm-headers),)
>> +    $(eval LOCAL_CFLAGS += -DHAVE_LLVM=0x0309 -DMESA_LLVM_VERSION_PATCH=0),) \
>> +  $(eval LOCAL_SHARED_LIBRARIES += libLLVM)
> Am I the only person getting tad confused by amount of brackets?
> As mentioned by Chih-Wei - a shell switch is not possible, but how
> about a test vague like the following?
>
> test "x$(MESA_ANDROID_MAJOR_VERSION)" = "xO" &&
>    $(eval LOCAL_CFLAGS += -DHAVE_LLVM=0x0309 -DMESA_LLVM_VERSION_PATCH=0)

Only possible if you put it into $(shell ...)
That gives me an idea. Maybe we ca do like

$(shell case "$(MESA_ANDROID_MAJOR_VERSION)" in \
            6) echo ... ;; \
            7) echo ... ;; \
            *)  echo ... ;; \
            esac)

I haven't really try it yet.

-- 
Chih-Wei
Android-x86 project
http://www.android-x86.org