[Buildroot] [PATCH v4, 1/1] package/grpc: fix build with uclibc on x86_64

[Arnout Vandecappelle]

On 02/06/2019 18:25, Fabrice Fontaine wrote:
> On x86_64 if GPR_MUSL_LIBC_COMPAT is not set, grpc tries to link with
> memcpy at GLIBC_2.2.5, see:
> https://github.com/grpc/grpc/blob/618a3f561d4a93f263cca23abad086ed8f4d5e86/src/core/lib/gpr/wrap_memcpy.cc
> 
> Add a new GPR_DISABLE_WRAPPED_MEMCPY to disable wrapped memory without
> changing CPU behavior
> 
> Fixes:
>  - http://autobuild.buildroot.org/results/20d6f2489a4e291a53bd514da66105eb607e1014
> 
> Signed-off-by: Fabrice Fontaine <fontaine.fabrice at gmail.com>

 Applied to master, thanks.

 Regards,
 Arnout

> ---
> Changes v3 -> v4:
>  - Add upstream URL for patch
>  - Fix typo in GPR_DISABLE_WRAPPED_MEMCPY
> 
> Changes v2 -> v3 (after review of Thomas Petazzoni and Arnout
> Vandecappelle):
>  - Add GPR_DISABLE_WRAPPED_MEMCPY variable instead of using
>    GPR_MUSL_LIBC_COMPAT to avoid changing CPU behavior
> 
> Changes v1 -> v2:
>  - Pass TARGET_CXXFLAGS to CMAKE_CXX_FLAGS
> 
>  ...py.cc-add-GPR_DISABLE_WRAPPED_MEMCPY.patch | 34 +++++++++++++++++++
>  package/grpc/grpc.mk                          |  8 +++++
>  2 files changed, 42 insertions(+)
>  create mode 100644 package/grpc/0003-wrap_memcpy.cc-add-GPR_DISABLE_WRAPPED_MEMCPY.patch
> 
> diff --git a/package/grpc/0003-wrap_memcpy.cc-add-GPR_DISABLE_WRAPPED_MEMCPY.patch b/package/grpc/0003-wrap_memcpy.cc-add-GPR_DISABLE_WRAPPED_MEMCPY.patch
> new file mode 100644
> index 0000000000..ad64804470
> --- /dev/null
> +++ b/package/grpc/0003-wrap_memcpy.cc-add-GPR_DISABLE_WRAPPED_MEMCPY.patch
> @@ -0,0 +1,34 @@
> +From be030314805137cd63b46ea6eaa702b608669910 Mon Sep 17 00:00:00 2001
> +From: Fabrice Fontaine <fontaine.fabrice at gmail.com>
> +Date: Sun, 2 Jun 2019 17:45:47 +0200
> +Subject: [PATCH] wrap_memcpy.cc: add GPR_DISABLE_WRAPPED_MEMCPY
> +
> +Add GPR_DISABLE_WRAPPED_MEMCPY to allow the user to disable wrapped
> +memcpy. This will fix build on x86_64 on musl/uclibc without changing
> +the cpu behavior.
> +
> +Fixes:
> + - http://autobuild.buildroot.org/results/20d6f2489a4e291a53bd514da66105eb607e1014
> +
> +Signed-off-by: Fabrice Fontaine <fontaine.fabrice at gmail.com>
> +[Upstream status: https://github.com/grpc/grpc/pull/19207]
> +---
> + src/core/lib/gpr/wrap_memcpy.cc | 2 +-
> + 1 file changed, 1 insertion(+), 1 deletion(-)
> +
> +diff --git a/src/core/lib/gpr/wrap_memcpy.cc b/src/core/lib/gpr/wrap_memcpy.cc
> +index 9b8608e056..38b76acf95 100644
> +--- a/src/core/lib/gpr/wrap_memcpy.cc
> ++++ b/src/core/lib/gpr/wrap_memcpy.cc
> +@@ -28,7 +28,7 @@
> + 
> + extern "C" {
> + #ifdef __linux__
> +-#if defined(__x86_64__) && !defined(GPR_MUSL_LIBC_COMPAT)
> ++#if defined(__x86_64__) && !defined(GPR_MUSL_LIBC_COMPAT) && !defined(GPR_DISABLE_WRAPPED_MEMCPY)
> + __asm__(".symver memcpy,memcpy at GLIBC_2.2.5");
> + void* __wrap_memcpy(void* destination, const void* source, size_t num) {
> +   return memcpy(destination, source, num);
> +-- 
> +2.20.1
> +
> diff --git a/package/grpc/grpc.mk b/package/grpc/grpc.mk
> index 9506e0268a..1a5f8855a1 100644
> --- a/package/grpc/grpc.mk
> +++ b/package/grpc/grpc.mk
> @@ -33,6 +33,14 @@ ifeq ($(BR2_TOOLCHAIN_HAS_LIBATOMIC),y)
>  GRPC_CONF_OPTS += -DCMAKE_EXE_LINKER_FLAGS=-latomic
>  endif
>  
> +# Set GPR_DISABLE_WRAPPED_MEMCPY otherwise build will fail on x86_64 with uclibc
> +# because grpc tries to link with memcpy at GLIBC_2.2.5
> +ifeq ($(BR2_x86_64):$(BR2_TOOLCHAIN_USES_GLIBC),y:)
> +GRPC_CONF_OPTS += \
> +	-DCMAKE_C_FLAGS="$(TARGET_CFLAGS) -DGPR_DISABLE_WRAPPED_MEMCPY" \
> +	-DCMAKE_CXX_FLAGS="$(TARGET_CXXFLAGS) -DGPR_DISABLE_WRAPPED_MEMCPY"
> +endif
> +
>  HOST_GRPC_CONF_OPTS = \
>  	-D_gRPC_CARES_LIBRARIES=cares \
>  	-DgRPC_CARES_PROVIDER=none \
>