toolchain: rework C++ options

Instead of having BR2_GCC_CROSS_CXX and BR2_INSTALL_LIBSTDCPP, with
BR2_GCC_CROSS_CXX not being visible (and therefore being useless),
let's just keep BR2_INSTALL_LIBSTDCPP to enable C++ in the toolchain
and install C++ libraries on the target.

We also take that opportunity to make BR2_INSTALL_LIBSTDCPP an hidden
option, which is selected by an option in Buildroot toolchain support
or an option in External toolchain support, just as we did for other
toolchain features.

Some work definitely remains to be done :

 - The name BR2_INSTALL_LIBSTDCPP is ugly, but we keep it for the
   moment in order to avoid changing all packages.

 - We should clarify the other language-related options (Fortran,
   Java, Objective-C, etc.).

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/Makefile.in

@@ -307,7 +307,7 @@ ifneq ($(BR2_INET_IPV6),y)
 DISABLE_IPV6= --disable-ipv6
 endif
 
-ifneq ($(BR2_GCC_CROSS_CXX),y)
+ifneq ($(BR2_INSTALL_LIBSTDCPP),y)
 TARGET_CONFIGURE_OPTS+=CXX=false
 endif
 

package/lzma/Config.in

@@ -1,6 +1,6 @@
 config BR2_PACKAGE_LZMA
 	bool "lzma"
-	depends on BR2_GCC_CROSS_CXX
+	depends on BR2_INSTALL_LIBSTDCPP
 	depends on BR2_DEPRECATED
 	help
 	  Lempel Ziv compression method (LZMA) is a compression
@@ -9,4 +9,4 @@ config BR2_PACKAGE_LZMA
 	  http://tukaani.org/lzma/
 
 comment "lzma requires a toolchain with C++ support"
-        depends on !BR2_GCC_CROSS_CXX && BR2_DEPRECATED
+        depends on !BR2_INSTALL_LIBSTDCPP && BR2_DEPRECATED

package/rpm/Config.in

@@ -25,11 +25,11 @@ config BR2_PACKAGE_RPM_BZIP2_PAYLOADS
 config BR2_PACKAGE_RPM_XZ_PAYLOADS
 	bool "support for xz payloads"
 	depends on BR2_PACKAGE_RPM
-	depends on BR2_GCC_CROSS_CXX
+	depends on BR2_INSTALL_LIBSTDCPP
 	help
 	  Support for xz payloads in RPM.
 
 comment "xz payload support requires a toolchain with c++ support"
-	depends on !BR2_GCC_CROSS_CXX
+	depends on !BR2_INSTALL_LIBSTDCPP
 
 

toolchain/gcc/gcc-uclibc-4.x.mk

@@ -67,7 +67,7 @@ GCC_STAGING_PREREQ+=$(STAGING_DIR)/usr/lib/libc.a
 GCC_TARGET_LANGUAGES:=c
 
 GCC_CROSS_LANGUAGES:=c
-ifeq ($(BR2_GCC_CROSS_CXX),y)
+ifeq ($(BR2_INSTALL_LIBSTDCPP),y)
 GCC_CROSS_LANGUAGES:=$(GCC_CROSS_LANGUAGES),c++
 endif
 ifeq ($(BR2_GCC_CROSS_FORTRAN),y)

toolchain/helpers.mk

@@ -220,7 +220,7 @@ check_arm_abi = \
 check_cplusplus = \
 	$(TARGET_CXX) -v > /dev/null 2>&1 ; \
 	if test $$? -ne 0 ; then \
-		echo "BR2_INSTALL_LIBSTDCPP is selected but C++ support not available in external toolchain" ; \
+		echo "C++ support is selected but is not available in external toolchain" ; \
 		exit 1 ; \
 	fi
 

toolchain/toolchain-buildroot/Config.in.2

@@ -51,6 +51,22 @@ config BR2_TOOLCHAIN_BUILDROOT_PROGRAM_INVOCATION
 	  (like tar and coreutils) utilize these for extra useful
 	  output, but in general are not required.
 
+config BR2_TOOLCHAIN_BUILDROOT_CXX
+	bool "Enable C++ support"
+	select BR2_INSTALL_LIBSTDCPP
+	depends on !(! BR2_GCC_SUPPORTS_FINEGRAINEDMTUNE && \
+		       BR2_TOOLCHAIN_BUILDROOT_LOCALE    && \
+		       BR2_UCLIBC_VERSION_0_9_31)
+	help
+	  Enable this option if you want your toolchain to support the
+	  C++ language and you want C++ libraries to be installed on
+	  your target system.
+
+comment "C++ support broken in uClibc 0.9.31 with locale enabled with gcc 4.2"
+	depends on !BR2_GCC_SUPPORTS_FINEGRAINEDMTUNE && \
+		    BR2_TOOLCHAIN_BUILDROOT_LOCALE    && \
+		    BR2_UCLIBC_VERSION_0_9_31
+
 source "toolchain/elf2flt/Config.in"
 source "toolchain/mklibs/Config.in"
 source "toolchain/sstrip/Config.in"

toolchain/toolchain-common.in

@@ -23,6 +23,9 @@ config BR2_ENABLE_LOCALE
 config BR2_PROGRAM_INVOCATION
 	bool
 
+config BR2_INSTALL_LIBSTDCPP
+	bool
+
 config BR2_ENABLE_LOCALE_PURGE
 	bool "Purge unwanted locales"
 	help
@@ -108,28 +111,6 @@ choice
 		depends on BR2_UCLIBC_VERSION_SNAPSHOT
 endchoice
 
-config BR2_GCC_CROSS_CXX
-	bool
-	help
-	  If you are building your own toolchain and want to build 
-	  a C++ cross-compiler this needs to be enabled.
-	  If you have an external binary toolchain that has a C++ compiler
-	  and you want to use it then you need to enable this option.
-
-config BR2_INSTALL_LIBSTDCPP
-	bool "Build/install c++ compiler and libstdc++?"
-	select BR2_GCC_CROSS_CXX
-	depends on !(! BR2_GCC_SUPPORTS_FINEGRAINEDMTUNE && BR2_ENABLE_LOCALE && BR2_UCLIBC_VERSION_0_9_31)
-	help
-	  If you are building your own toolchain and want to build and install
-	  the C++ compiler and library then you need to enable this option.
-	  If you have an external toolchain that has been built with C++ 
-	  support and you want to use the compiler / library then you need 
-	  to select this option.
-
-comment "C++ support broken in uClibc 0.9.31 with locale enabled with gcc 4.2"
-	depends on !BR2_GCC_SUPPORTS_FINEGRAINEDMTUNE && BR2_ENABLE_LOCALE && BR2_UCLIBC_VERSION_0_9_31
-
 config BR2_TARGET_OPTIMIZATION
 	string "Target Optimizations"
 	default "-pipe"

toolchain/toolchain-crosstool-ng/Config.in

@@ -98,4 +98,12 @@ config BR2_TOOLCHAIN_CTNG_uClibc_PROGRAM_INVOCATION
 
 endif # BR2_TOOLCHAIN_CTNG_uClibc
 
+config BR2_TOOLCHAIN_CTNG_CXX
+	bool "Enable C++ support"
+	select BR2_INSTALL_LIBSTDCPP
+	help
+	  Enable this option if you want your toolchain to support the
+	  C++ language and you want C++ libraries to be installed on
+	  your target system.
+
 endif # BR2_TOOLCHAIN_CTNG

toolchain/toolchain-crosstool-ng/crosstool-ng.mk

@@ -207,7 +207,7 @@ CTNG_FIX_DOT_CONFIG_SED += s:^(CT_CC_PKGVERSION)="(.*)":\1="crosstool-NG $(CTNG_
 ifneq ($(call qstrip,$(BR2_PACKAGE_GDB_SERVER))$(call qstrip,$(BR2_PACKAGE_GDB_HOST)),)
 CTNG_FIX_DOT_CONFIG_SED += s:^(CT_DEBUG_gdb)=.*:\# \1 is not set:;
 endif
-ifneq ($(call qstrip,$(BR2_INSTALL_LIBSTDCPP)),)
+ifeq ($(call qstrip,$(BR2_TOOLCHAIN_CTNG_CXX)),y)
 CTNG_FIX_DOT_CONFIG_SED += s:^\# (CT_CC_LANG_CXX) is not set:\1=y:;
 else
 CTNG_FIX_DOT_CONFIG_SED += s:^(CT_CC_LANG_CXX)=.*:\# \1 is not set:;

toolchain/toolchain-external/Config.in

@@ -7,6 +7,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_ARM201009
 	bool "CodeSourcery ARM 2010.09"
 	depends on BR2_arm
 	select BR2_TOOLCHAIN_EXTERNAL_GLIBC
+	select BR2_INSTALL_LIBSTDCPP
 	help
 	  Toolchain for the ARM architecture, from CodeSourcery. It
 	  uses gcc 4.5.1, binutils 2.20, glibc 2.11 and gdb 7.2.50,
@@ -20,6 +21,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_ARM2010Q1
 	bool "CodeSourcery ARM 2010q1"
 	depends on BR2_arm
 	select BR2_TOOLCHAIN_EXTERNAL_GLIBC
+	select BR2_INSTALL_LIBSTDCPP
 	help
 	  Toolchain for the ARM architecture, from CodeSourcery. It
 	  uses gcc 4.4.1, binutils 2.19, glibc 2.11, gdb 7.0.50 and
@@ -33,6 +35,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_ARM2009Q1
 	bool "CodeSourcery ARM 2009q1"
 	depends on BR2_arm
 	select BR2_TOOLCHAIN_EXTERNAL_GLIBC
+	select BR2_INSTALL_LIBSTDCPP
 	help
 	  Toolchain for the ARM architecture, from CodeSourcery. It
 	  uses gcc 4.3.3, binutils 2.19, glibc 2.8 and gdb 6.8 and
@@ -46,6 +49,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS44
 	bool "CodeSourcery MIPS 4.4"
 	depends on BR2_mips || BR2_mipsel
 	select BR2_TOOLCHAIN_EXTERNAL_GLIBC
+	select BR2_INSTALL_LIBSTDCPP
 	help
 	  Toolchain for the MIPS architecture, from CodeSourcery. It
 	  uses gcc 4.4.1, binutils 2.19, glibc 2.11, uClibc 0.9.30 and
@@ -68,6 +72,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_POWERPC201009
 	bool "CodeSoucery PowerPC 2010.09"
 	depends on BR2_powerpc
 	select BR2_TOOLCHAIN_EXTERNAL_GLIBC
+	select BR2_INSTALL_LIBSTDCPP
 	help
 	  Toolchain for the PowerPC architecture, from
 	  CodeSourcery. It uses gcc 4.5.1, binutils 2.20, glibc 2.11,
@@ -85,6 +90,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_SH201009
 	bool "CodeSoucery PowerPC 2010.09"
 	depends on BR2_sh
 	select BR2_TOOLCHAIN_EXTERNAL_GLIBC
+	select BR2_INSTALL_LIBSTDCPP
 	help
 	  Toolchain for the SuperH architecture, from CodeSourcery. It
 	  uses gcc 4.5.1, binutils 2.20, glibc 2.11, uClibc 0.9.30,
@@ -216,6 +222,14 @@ config BR2_TOOLCHAIN_EXTERNAL_PROGRAM_INVOCATION
 
 endif # BR2_TOOLCHAIN_EXTERNAL_CUSTOM_UCLIBC
 
+config BR2_TOOLCHAIN_EXTERNAL_CXX
+	bool "Toolchain has C++ support?"
+	select BR2_INSTALL_LIBSTDCPP
+	help
+	  Select this option if your external toolchain has C++
+	  support. If you don't know, leave the default value,
+	  Buildroot will tell you if it's correct or not.
+
 endif # BR2_TOOLCHAIN_EXTERNAL_CUSTOM
 
 endif # BR2_TOOLCHAIN_EXTERNAL