During cross compiling, CPP is being set to the target compiler even for
build targets. As an example, when building a cross compiler targetting
mingw, the config.log for libiberty in
build.x86_64-pokysdk-mingw32.i586-poky-linux/build-x86_64-linux/libiberty/config.log
shows:
configure:3786: checking how to run the C preprocessor
configure:3856: result: x86_64-pokysdk-mingw32-gcc -E
--sysroot=[sysroot]/x86_64-nativesdk-mingw32-pokysdk-mingw32
configure:3876: x86_64-pokysdk-mingw32-gcc -E
--sysroot=[sysroot]/x86_64-nativesdk-mingw32-pokysdk-mingw32 conftest.c
configure:3876: $? = 0
This is libiberty being built for the build environment, not the target one
(i.e. in build-x86_64-linux). As such it should be using the build environment's
gcc and not the target one. In the mingw case the system headers are quite
different leading to build failures related to not being able to include a
process.h file for pem-unix.c.
Fix this by using CC_FOR_BUILD instead of CC. Ultimately a CPP_FOR_BUILD
could be defined but CC_FOR_BUILD seems at least more correct and is a simpler
fix.
2021-10-26 Richard Purdie <richard.pur...@linuxfoundation.org>
Changelog:
* Makefile.in: Use CC_FOR_BUILD as CPP for build targets
to avoid host/target contamination
Signed-off-by: Richard Purdie <richard.pur...@linuxfoundation.org>
---
Makefile.in | 1 +
1 file changed, 1 insertion(+)
diff --git a/Makefile.in b/Makefile.in
index 34b2d89660d..f4815d7e75f 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -152,6 +152,7 @@ BUILD_EXPORTS = \
AR="$(AR_FOR_BUILD)"; export AR; \
AS="$(AS_FOR_BUILD)"; export AS; \
CC="$(CC_FOR_BUILD)"; export CC; \
+ CPP="$(CC_FOR_BUILD) -E"; export CPP; \
CFLAGS="$(CFLAGS_FOR_BUILD)"; export CFLAGS; \
CONFIG_SHELL="$(SHELL)"; export CONFIG_SHELL; \
CXX="$(CXX_FOR_BUILD)"; export CXX; \
--
2.32.0
