[Buildroot] [PATCH 4/5] toolchain-external: align library locations in target and staging dir

[Romain Naour <romain.naour@gmail.com>]

Hi Thomas, all,

Le 12/02/2016 20:20, Thomas De Schampheleire a ?crit :
> From: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
> 
> The toolchain-external logic is roughly:
> - populate the staging dir by rsyncing the entire ${ARCH_LIB_DIR} and
>   usr/${ARCH_LIB_DIR} from sysroot.
> - populate the target dir by explictly copying some libraries from sysroot
>   into target/lib and some other libraries in target/usr/lib, the split
>   being hardcoded into buildroot regardless of the location in the sysroot.
> 
> This means that a library libfoo could be located in:
>   staging/lib/libfoo.so
>   target/usr/lib/libfoo.so
> 
> When debugging an application that links against this library, gdb will
> fruitlessly search for 'usr/lib/libfoo.so' in staging, and then suggest to
> use 'set solib-search-path' which is a hack, really.
> 
> To solve the problem, we need to make sure that libraries from the toolchain
> are installed in the same relative location in staging and target.
> Achieve this by:
> - replacing the convoluted search for libraries using for+find in sysroot
>   with a simple find in staging.
> - determining DESTDIR for each library individually based on the location in
>   staging.
> - treating LIB_EXTERNAL_LIBS and USR_LIB_EXTERNAL_LIBS equivalently
> 
> These changes also allow for the removal of most arguments to
> copy_toolchain_lib_root in the method itself and their callers.
> 
> Test procedure:
> - set configuration for a given toolchain
> - make clean toolchain
> - find output/target | sort > /tmp/out-before
> - apply patch
> - make clean toolchain
> - find output/target | sort > /tmp/out-after
> - diff -u /tmp/out-before /tmp/out-after
> 
> The only changes should be some libraries moving from lib to usr/lib or vice
> versa. Notable examples being libstdc++ and libatomic.

Using an arbitrary toolchain (BR2_TOOLCHAIN_EXTERNAL_LINARO_AARCH64 2015.11)

The only diff is:

before:
output/target/usr/lib/libstdc++.so.6
output/target/usr/lib/libstdc++.so.6.0.21
output/target/usr/lib/libstdc++.so.6.0.21-gdb.py

after:
output/target/lib/libstdc++.so.6
output/target/lib/libstdc++.so.6.0.21
output/target/lib/libstdc++.so.6.0.21-gdb.py

Now libstdc++.so.6 is located in the same directory on the target than the
toolchain sysroot (/lib/libstdc++.so.6).

toolchain sysroot:
ext-toolchain/aarch64-linux-gnu/libc/lib/libstdc++.so.6.0.21
ext-toolchain/aarch64-linux-gnu/libc/lib/libstdc++.so.6

Reviewed-by: Romain Naour <romain.naour@gmail.com>

Best regards,
Romain

> 
> Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
> ---
>  package/glibc/glibc.mk                             |  2 +-
>  toolchain/helpers.mk                               | 57 ++--------------------
>  toolchain/toolchain-external/toolchain-external.mk | 39 ++++-----------
>  3 files changed, 15 insertions(+), 83 deletions(-)
> 
> Test notes:
> I have executed the mentioned test procedure for all external toolchains
> listed on http://autobuild.buildroot.org/toolchains/configs/, for the x86
> ARMv7a Thumb2 EABIhf Linaro toolchain, and for an internal glibc toolchain.
> An x86_64 qemu image was booted, both with internal and external toolchain.
> 
> 
> diff --git a/package/glibc/glibc.mk b/package/glibc/glibc.mk
> index e60575f..bcec47f 100644
> --- a/package/glibc/glibc.mk
> +++ b/package/glibc/glibc.mk
> @@ -117,7 +117,7 @@ endif
>  
>  define GLIBC_INSTALL_TARGET_CMDS
>  	for libs in $(GLIBC_LIBS_LIB); do \
> -		$(call copy_toolchain_lib_root,$(STAGING_DIR)/,,lib,$$libs,/lib) ; \
> +		$(call copy_toolchain_lib_root,$$libs) ; \
>  	done
>  endef
>  
> diff --git a/toolchain/helpers.mk b/toolchain/helpers.mk
> index ee878e8..d5dc16f 100644
> --- a/toolchain/helpers.mk
> +++ b/toolchain/helpers.mk
> @@ -6,62 +6,15 @@
>  # toolchain logic, and the glibc package, so care must be taken when
>  # changing this function.
>  #
> -# Most toolchains (CodeSourcery ones) have their libraries either in
> -# /lib or /usr/lib relative to their ARCH_SYSROOT_DIR, so we search
> -# libraries in:
> -#
> -#  $${ARCH_LIB_DIR}
> -#  usr/$${ARCH_LIB_DIR}
> -#
> -# Buildroot toolchains, however, have basic libraries in /lib, and
> -# libstdc++/libgcc_s in /usr/<target-name>/lib(64), so we also need to
> -# search libraries in:
> -#
> -#  usr/$(TOOLCHAIN_EXTERNAL_PREFIX)/$${ARCH_LIB_DIR}
> -#
> -# Linaro toolchains have most libraries in lib/<target-name>/, so we
> -# need to search libraries in:
> -#
> -#  $${ARCH_LIB_DIR}/$(TOOLCHAIN_EXTERNAL_PREFIX)
> -#
> -# And recent Linaro toolchains have the GCC support libraries
> -# (libstdc++, libgcc_s, etc.) into a separate directory, outside of
> -# the sysroot, that we called the "SUPPORT_LIB_DIR", into which we
> -# need to search as well.
> -#
> -# Thanks to ARCH_LIB_DIR we also take into account toolchains that
> -# have the libraries in lib64 and usr/lib64.
> -#
> -# Please be very careful to check the major toolchain sources:
> -# Buildroot, Crosstool-NG, CodeSourcery and Linaro before doing any
> -# modification on the below logic.
> -#
> -# $1: arch specific sysroot directory
> -# $2: support libraries directory (can be empty)
> -# $3: library directory ('lib' or 'lib64') from which libraries must be copied
> -# $4: library name
> -# $5: destination directory of the libary, relative to $(TARGET_DIR)
> +# $1: library name
>  #
>  copy_toolchain_lib_root = \
> -	ARCH_SYSROOT_DIR="$(strip $1)"; \
> -	SUPPORT_LIB_DIR="$(strip $2)" ; \
> -	ARCH_LIB_DIR="$(strip $3)" ; \
> -	LIB="$(strip $4)"; \
> -	DESTDIR="$(strip $5)" ; \
> +	LIB="$(strip $1)"; \
>  \
> -	for dir in \
> -		$${ARCH_SYSROOT_DIR}/$${ARCH_LIB_DIR}/$(TOOLCHAIN_EXTERNAL_PREFIX) \
> -		$${ARCH_SYSROOT_DIR}/usr/$(TOOLCHAIN_EXTERNAL_PREFIX)/$${ARCH_LIB_DIR} \
> -		$${ARCH_SYSROOT_DIR}/$${ARCH_LIB_DIR} \
> -		$${ARCH_SYSROOT_DIR}/usr/$${ARCH_LIB_DIR} \
> -		$${SUPPORT_LIB_DIR} ; do \
> -		LIBPATHS=`find $${dir} -maxdepth 1 -name "$${LIB}" 2>/dev/null` ; \
> -		if test -n "$${LIBPATHS}" ; then \
> -			break ; \
> -		fi \
> -	done ; \
> -	mkdir -p $(TARGET_DIR)/$${DESTDIR}; \
> +	LIBPATHS=`find $(STAGING_DIR) -follow -name "$${LIB}" 2>/dev/null` ; \
>  	for LIBPATH in $${LIBPATHS} ; do \
> +		DESTDIR=`echo $${LIBPATH} | sed "s,^$(STAGING_DIR)/,," | xargs dirname` ; \
> +		mkdir -p $(TARGET_DIR)/$${DESTDIR}; \
>  		while true ; do \
>  			LIBNAME=`basename $${LIBPATH}`; \
>  			LIBDIR=`dirname $${LIBPATH}` ; \
> diff --git a/toolchain/toolchain-external/toolchain-external.mk b/toolchain/toolchain-external/toolchain-external.mk
> index d5445e5..a333c32 100644
> --- a/toolchain/toolchain-external/toolchain-external.mk
> +++ b/toolchain/toolchain-external/toolchain-external.mk
> @@ -585,24 +585,16 @@ endef
>  #                       our sysroot, and the directory will also be
>  #                       considered when searching libraries for copy
>  #                       to the target filesystem.
> +#
> +# Please be very careful to check the major toolchain sources:
> +# Buildroot, Crosstool-NG, CodeSourcery and Linaro
> +# before doing any modification on the below logic.
>  
>  define TOOLCHAIN_EXTERNAL_INSTALL_TARGET_LIBS
> -	$(Q)ARCH_SYSROOT_DIR="$(call toolchain_find_sysroot,$(TOOLCHAIN_EXTERNAL_CC) $(TOOLCHAIN_EXTERNAL_CFLAGS))" ; \
> -	ARCH_LIB_DIR="$(call toolchain_find_libdir,$(TOOLCHAIN_EXTERNAL_CC) $(TOOLCHAIN_EXTERNAL_CFLAGS))" ; \
> -	SUPPORT_LIB_DIR="" ; \
> -	if test `find $${ARCH_SYSROOT_DIR} -name 'libstdc++.a' | wc -l` -eq 0 ; then \
> -		LIBSTDCPP_A_LOCATION=$$(LANG=C $(TOOLCHAIN_EXTERNAL_CC) $(TOOLCHAIN_EXTERNAL_CFLAGS) -print-file-name=libstdc++.a) ; \
> -		if [ -e "$${LIBSTDCPP_A_LOCATION}" ]; then \
> -			SUPPORT_LIB_DIR=`readlink -f $${LIBSTDCPP_A_LOCATION} | sed -r -e 's:libstdc\+\+\.a::'` ; \
> -		fi ; \
> -	fi ; \
> -	if test -z "$(BR2_STATIC_LIBS)" ; then \
> +	$(Q)if test -z "$(BR2_STATIC_LIBS)" ; then \
>  		$(call MESSAGE,"Copying external toolchain libraries to target...") ; \
> -		for libs in $(LIB_EXTERNAL_LIBS); do \
> -			$(call copy_toolchain_lib_root,$${ARCH_SYSROOT_DIR},$${SUPPORT_LIB_DIR},$${ARCH_LIB_DIR},$$libs,/lib); \
> -		done ; \
> -		for libs in $(USR_LIB_EXTERNAL_LIBS); do \
> -			$(call copy_toolchain_lib_root,$${ARCH_SYSROOT_DIR},$${SUPPORT_LIB_DIR},$${ARCH_LIB_DIR},$$libs,/usr/lib); \
> +		for libs in $(LIB_EXTERNAL_LIBS) $(USR_LIB_EXTERNAL_LIBS); do \
> +			$(call copy_toolchain_lib_root,$$libs); \
>  		done ; \
>  	fi
>  endef
> @@ -671,21 +663,8 @@ define TOOLCHAIN_EXTERNAL_INSTALL_SYSROOT_LIBS_BFIN_FDPIC
>  endef
>  define TOOLCHAIN_EXTERNAL_INSTALL_BFIN_FDPIC
>  	$(Q)$(call MESSAGE,"Install external toolchain FDPIC libraries to target...") ; \
> -	FDPIC_EXTERNAL_CC=$(dir $(TOOLCHAIN_EXTERNAL_CC))/../../bfin-linux-uclibc/bin/bfin-linux-uclibc-gcc ; \
> -	FDPIC_SYSROOT_DIR="$(call toolchain_find_sysroot,$${FDPIC_EXTERNAL_CC} $(TOOLCHAIN_EXTERNAL_CFLAGS))" ; \
> -	FDPIC_LIB_DIR="$(call toolchain_find_libdir,$${FDPIC_EXTERNAL_CC} $(TOOLCHAIN_EXTERNAL_CFLAGS))" ; \
> -	FDPIC_SUPPORT_LIB_DIR="" ; \
> -	if test `find $${FDPIC_SYSROOT_DIR} -name 'libstdc++.a' | wc -l` -eq 0 ; then \
> -	        FDPIC_LIBSTDCPP_A_LOCATION=$$(LANG=C $${FDPIC_EXTERNAL_CC} $(TOOLCHAIN_EXTERNAL_CFLAGS) -print-file-name=libstdc++.a) ; \
> -	        if [ -e "$${FDPIC_LIBSTDCPP_A_LOCATION}" ]; then \
> -	                FDPIC_SUPPORT_LIB_DIR=`readlink -f $${FDPIC_LIBSTDCPP_A_LOCATION} | sed -r -e 's:libstdc\+\+\.a::'` ; \
> -	        fi ; \
> -	fi ; \
> -	for libs in $(LIB_EXTERNAL_LIBS); do \
> -	        $(call copy_toolchain_lib_root,$${FDPIC_SYSROOT_DIR},$${FDPIC_SUPPORT_LIB_DIR},$${FDPIC_LIB_DIR},$$libs,/lib); \
> -	done ; \
> -	for libs in $(USR_LIB_EXTERNAL_LIBS); do \
> -	        $(call copy_toolchain_lib_root,$${FDPIC_SYSROOT_DIR},$${FDPIC_SUPPORT_LIB_DIR},$${FDPIC_LIB_DIR},$$libs,/usr/lib); \
> +	for libs in $(LIB_EXTERNAL_LIBS) $(USR_LIB_EXTERNAL_LIBS); do \
> +		$(call copy_toolchain_lib_root,$$libs); \
>  	done
>  endef
>  endif
>