[Buildroot] [PATCH v2] sh4: fix toolchain creation

[Buildroot] [PATCH v2] sh4: fix toolchain creation

[Waldemar Brodkorb]

The Linux kernel does force compile with -m4-nofpu, which is only
available when building a multilib toolchain.
The interesting part here is, that buildroot use --disable-multilib for
gcc configure, but enables --with-multilib-list=m4,m4-nofpu in
the default configuration for Qemu targeting r2d emulation.
This results in a toolchain, which can be used for the kernel and
for userland without creating a multilib toolchain with different
kinds of libgcc version. In the multilib case there would be
subdirectories created (!m4 and m4-nofpu). As buildroot uses a
short version of toolchain creation, a multilib enabled gcc build
fails when creating libgcc.

So the best solution is to just keep multilib disabled, but always
add --with-multilib-list when sh4/sh4eb/sh4a/sh4aeb is choosen.

Tested with sh4/sh4a toolchain build and qemu defconfig with
gcc 4.8.x/4.9.x (with and without C++ enabled), uClibc and glibc.

CAUTION: uClibc/uClibc-ng does not work for sh4a/sh4aeb.

Signed-off-by: Waldemar Brodkorb <wbx@openadk.org>
---
 - fix build when C++ is enabled
 - tested with sh4a/sh4aeb

---
 configs/qemu_sh4_r2d_defconfig     |    4 ----
 package/gcc/gcc-final/gcc-final.mk |   22 +++++++++++++++++-----
 2 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/configs/qemu_sh4_r2d_defconfig b/configs/qemu_sh4_r2d_defconfig
index 88bf914..586c400 100644
--- a/configs/qemu_sh4_r2d_defconfig
+++ b/configs/qemu_sh4_r2d_defconfig
@@ -10,10 +10,6 @@ BR2_TARGET_GENERIC_GETTY_PORT="ttySC1"
 BR2_TARGET_ROOTFS_EXT2=y
 # BR2_TARGET_ROOTFS_TAR is not set
 
-# The kernel wants to use the -m4-nofpu option to make sure that it
-# doesn't use floating point operations.
-BR2_EXTRA_GCC_CONFIG_OPTIONS="--with-multilib-list=m4,m4-nofpu"
-
 # Lock to 3.19 headers to avoid breaking with newer kernels
 BR2_KERNEL_HEADERS_VERSION=y
 BR2_DEFAULT_KERNEL_VERSION="3.19"
diff --git a/package/gcc/gcc-final/gcc-final.mk b/package/gcc/gcc-final/gcc-final.mk
index d76eb31..c5ec4dd 100644
--- a/package/gcc/gcc-final/gcc-final.mk
+++ b/package/gcc/gcc-final/gcc-final.mk
@@ -52,6 +52,18 @@ HOST_GCC_FINAL_CONF_OPTS = \
 	--enable-poison-system-directories \
 	--with-build-time-tools=$(HOST_DIR)/usr/$(GNU_TARGET_NAME)/bin
 
+LIB_DIR := lib*
+# The kernel wants to use the -m4-nofpu option to make sure that it
+# doesn't use floating point operations.
+ifeq ($(BR2_sh4)$(BR2_sh4eb),y)
+HOST_GCC_FINAL_CONF_OPTS += "--with-multilib-list=m4,m4-nofpu"
+LIB_DIR := lib/!m4*
+endif
+ifeq ($(BR2_sh4a)$(BR2_sh4aeb),y)
+HOST_GCC_FINAL_CONF_OPTS += "--with-multilib-list=m4a,m4a-nofpu"
+LIB_DIR := lib/!m4*
+endif
+
 # Disable shared libs like libstdc++ if we do static since it confuses linking
 ifeq ($(BR2_STATIC_LIBS),y)
 HOST_GCC_FINAL_CONF_OPTS += --disable-shared
@@ -110,9 +122,9 @@ endif
 # Cannot use the HOST_GCC_FINAL_USR_LIBS mechanism below, because we want
 # libgcc_s to be installed in /lib and not /usr/lib.
 define HOST_GCC_FINAL_INSTALL_LIBGCC
-	-cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/lib*/libgcc_s* \
+	-cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/$(LIB_DIR)/libgcc_s* \
 		$(STAGING_DIR)/lib/
-	-cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/lib*/libgcc_s* \
+	-cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/$(LIB_DIR)/libgcc_s* \
 		$(TARGET_DIR)/lib/
 endef
 
@@ -140,7 +152,7 @@ endif
 ifneq ($(HOST_GCC_FINAL_USR_LIBS),)
 define HOST_GCC_FINAL_INSTALL_STATIC_LIBS
 	for i in $(HOST_GCC_FINAL_USR_LIBS) ; do \
-		cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/lib*/$${i}.a \
+		cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/$(LIB_DIR)/$${i}.a \
 			$(STAGING_DIR)/usr/lib/ ; \
 	done
 endef
@@ -148,9 +160,9 @@ endef
 ifeq ($(BR2_STATIC_LIBS),)
 define HOST_GCC_FINAL_INSTALL_SHARED_LIBS
 	for i in $(HOST_GCC_FINAL_USR_LIBS) ; do \
-		cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/lib*/$${i}.so* \
+		cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/$(LIB_DIR)/$${i}.so* \
 			$(STAGING_DIR)/usr/lib/ ; \
-		cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/lib*/$${i}.so* \
+		cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/$(LIB_DIR)/$${i}.so* \
 			$(TARGET_DIR)/usr/lib/ ; \
 	done
 endef
-- 
1.7.10.4

[Buildroot] [PATCH v2] sh4: fix toolchain creation

[Thomas Petazzoni]

Waldemar,

Thanks for this new iteration!

On Tue, 7 Apr 2015 22:11:25 +0200, Waldemar Brodkorb wrote:

> CAUTION: uClibc/uClibc-ng does not work for sh4a/sh4aeb.

So we should add the appropriate Config.in conditions to make sure
uClibc and uClibc-ng cannot be selected on sh4a*.

> +LIB_DIR := lib*

The scope of variables is global in Buildroot, so all variables should
be prefixed by the name of the package, i.e:

HOST_GCC_FINAL_GCC_LIB_DIR = lib*

Also, no reason to use := here, so use = instead.

> +# The kernel wants to use the -m4-nofpu option to make sure that it
> +# doesn't use floating point operations.
> +ifeq ($(BR2_sh4)$(BR2_sh4eb),y)
> +HOST_GCC_FINAL_CONF_OPTS += "--with-multilib-list=m4,m4-nofpu"
> +LIB_DIR := lib/!m4*
> +endif
> +ifeq ($(BR2_sh4a)$(BR2_sh4aeb),y)
> +HOST_GCC_FINAL_CONF_OPTS += "--with-multilib-list=m4a,m4a-nofpu"
> +LIB_DIR := lib/!m4*
> +endif
> +
>  # Disable shared libs like libstdc++ if we do static since it confuses linking
>  ifeq ($(BR2_STATIC_LIBS),y)
>  HOST_GCC_FINAL_CONF_OPTS += --disable-shared
> @@ -110,9 +122,9 @@ endif
>  # Cannot use the HOST_GCC_FINAL_USR_LIBS mechanism below, because we want
>  # libgcc_s to be installed in /lib and not /usr/lib.
>  define HOST_GCC_FINAL_INSTALL_LIBGCC
> -	-cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/lib*/libgcc_s* \
> +	-cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/$(LIB_DIR)/libgcc_s* \
>  		$(STAGING_DIR)/lib/
> -	-cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/lib*/libgcc_s* \
> +	-cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/$(LIB_DIR)/libgcc_s* \
>  		$(TARGET_DIR)/lib/
>  endef
>  
> @@ -140,7 +152,7 @@ endif
>  ifneq ($(HOST_GCC_FINAL_USR_LIBS),)
>  define HOST_GCC_FINAL_INSTALL_STATIC_LIBS
>  	for i in $(HOST_GCC_FINAL_USR_LIBS) ; do \
> -		cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/lib*/$${i}.a \
> +		cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/$(LIB_DIR)/$${i}.a \
>  			$(STAGING_DIR)/usr/lib/ ; \
>  	done
>  endef
> @@ -148,9 +160,9 @@ endef
>  ifeq ($(BR2_STATIC_LIBS),)
>  define HOST_GCC_FINAL_INSTALL_SHARED_LIBS
>  	for i in $(HOST_GCC_FINAL_USR_LIBS) ; do \
> -		cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/lib*/$${i}.so* \
> +		cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/$(LIB_DIR)/$${i}.so* \
>  			$(STAGING_DIR)/usr/lib/ ; \
> -		cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/lib*/$${i}.so* \
> +		cp -dpf $(HOST_DIR)/usr/$(GNU_TARGET_NAME)/$(LIB_DIR)/$${i}.so* \
>  			$(TARGET_DIR)/usr/lib/ ; \
>  	done
>  endef

Maybe we can have a variable that shortens
$(HOST_DIR)/usr/$(GNU_TARGET_NAME)/$(LIB_DIR)/. Maybe this is actually
what HOST_GCC_FINAL_GCC_LIB_DIR should point to?

Thanks,

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

[Buildroot] [PATCH v2] sh4: fix toolchain creation

[Rob Landley]

On Tue, Apr 7, 2015 at 3:11 PM, Waldemar Brodkorb <wbx@openadk.org> wrote:
> The Linux kernel does force compile with -m4-nofpu, which is only
> available when building a multilib toolchain.
...
> CAUTION: uClibc/uClibc-ng does not work for sh4a/sh4aeb.

Does musl work with that? (The uClibc project is moribund verging on
dead, musl is the obvious replacement. I'm trying to get sh2 support
working in musl but there are toolchain issues I need to deal with
first...)

Rob