diff mbox

[3/9] toolchain-external: add support for gcc version dependency

Message ID 1438711241-31792-4-git-send-email-thomas.petazzoni@free-electrons.com
State Accepted
Headers show

Commit Message

Thomas Petazzoni Aug. 4, 2015, 6 p.m. UTC 
This commit wires up the gcc version dependency mechanism in the
external toolchain backend. To do so, it:

 * Changes the definition of all pre-defined external toolchain
   profiles to select the appropriate BR2_TOOLCHAIN_GCC_AT_LEAST_*
   option.

 * For custom external toolchains, provides a visible Config.in
   "choice" to select the gcc version used in the external toolchain.

 * Adds a new check_gcc_version function, that verifies that the real
   gcc version found in the external toolchain matches the one
   declared in the Buildroot configuration.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
 toolchain/helpers.mk                               | 22 +++++++
 toolchain/toolchain-external/Config.in             | 70 ++++++++++++++++++++++
 toolchain/toolchain-external/toolchain-external.mk |  2 +
 3 files changed, 94 insertions(+)

Comments

Yann E. MORIN Aug. 4, 2015, 7:49 p.m. UTC | #1 
Thomas, all,

On 2015-08-04 20:00 +0200, Thomas Petazzoni spake thusly:
> This commit wires up the gcc version dependency mechanism in the
> external toolchain backend. To do so, it:
> 
>  * Changes the definition of all pre-defined external toolchain
>    profiles to select the appropriate BR2_TOOLCHAIN_GCC_AT_LEAST_*
>    option.
> 
>  * For custom external toolchains, provides a visible Config.in
>    "choice" to select the gcc version used in the external toolchain.
> 
>  * Adds a new check_gcc_version function, that verifies that the real
>    gcc version found in the external toolchain matches the one
>    declared in the Buildroot configuration.
> 
> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> ---
>  toolchain/helpers.mk                               | 22 +++++++
>  toolchain/toolchain-external/Config.in             | 70 ++++++++++++++++++++++
>  toolchain/toolchain-external/toolchain-external.mk |  2 +
>  3 files changed, 94 insertions(+)
> 
> diff --git a/toolchain/helpers.mk b/toolchain/helpers.mk
> index 895f3f1..038939c 100644
> --- a/toolchain/helpers.mk
> +++ b/toolchain/helpers.mk
> @@ -175,6 +175,28 @@ check_kernel_headers_version = \
>  	fi
>  
>  #
> +# Check the specific gcc version actually matches the version in the
> +# toolchain
> +#
> +# $1: path to gcc
> +# $2: expected gcc version
> +#
> +# The first 'sed' removes everything but the last word of the line,
> +# which contains the gcc version.

That's not true for the BR2_TOOLCHAIN_EXTERNAL_LINARO_AARCH64 toolchain:

    $ ./host/opt/ext-toolchain/bin/aarch64-linux-gnu-gcc --version
    aarch64-linux-gnu-gcc (crosstool-NG linaro-1.13.1-4.9-2014.09 -
    Linaro GCC 4.9-2014.09) 4.9.2 20140904 (prerelease)

Here's a better sed-expr that should match it too, as well as the other
gcc versions; we'll make the assumption that the version string is right
after the first closing parenthesis:

    sed -r -e '1!d; s/^[^)]+\) ([^[:space:]]+).*/\1/; s/\.[[:digit:]]+$//;'

Explanations;

  - 1!d
      - delete if not line 1  (i.e. your 'head -n1')

  - s/^[^)]+\) ([^[:space:]]+).*/\1/
      - eat all until the first ')' character followed by a space
      - match as many non-space chars as possible
      - eat all the remaining chars on the line
      - replace by the matched expression

  - s/\.[[:digit:]]+$//
      - eat a dot followed by as many digits as possible up to the end
        of line
      - replace with nothing

Notes:
  - it's an extended regexp, because [...] is not valid in a standard
    regexp, and doing without it is much more complex;
  - it's a single sed invocation, no need for head or many sed calls.

Regards,
Yann E. MORIN.

> +# The second 'sed' removes the last digit of the version (i.e 4.9.3
> +# becomes 4.9 and 5.1 becomes 5), which allows to match on the gcc
> +# major version only.
> +#
> +check_gcc_version = \
> +	expected_version="$(strip $2)" ; \
> +	real_version=`$(1) --version | head -1 | sed 's%.* %%g' | sed 's%\(.*\)\.[0-9]%\1%'` ; \
> +	if [ "$${real_version}" != "$${expected_version}" ] ; then \
> +		echo "Incorrect selection of gcc version: expected $${expected_version}, got $${real_version}" ; \
> +		exit 1 ; \
> +	fi
> +
> +#
>  # Check the availability of a particular glibc feature. This function
>  # is used to check toolchain options that are always supported by
>  # glibc, so we simply check that the corresponding option is properly
> diff --git a/toolchain/toolchain-external/Config.in b/toolchain/toolchain-external/Config.in
> index e70989e..310ea99 100644
> --- a/toolchain/toolchain-external/Config.in
> +++ b/toolchain/toolchain-external/Config.in
> @@ -18,6 +18,7 @@ config BR2_TOOLCHAIN_EXTERNAL_LINARO_ARM
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_1
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_9
>  	help
>  	  Linaro toolchain for the ARM architecture. It uses Linaro
>  	  GCC 2014.09 (based on gcc 4.9), Linaro GDB 2013.10 (based on
> @@ -44,6 +45,7 @@ config BR2_TOOLCHAIN_EXTERNAL_LINARO_ARMEB
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_1
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_9
>  	help
>  	  Linaro toolchain for the ARM big endian architecture. It
>  	  uses Linaro GCC 2014.09 (based on gcc 4.9), Linaro GDB
> @@ -69,6 +71,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_ARM201405
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_13
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
>  	help
>  	  Sourcery CodeBench toolchain for the ARM architecture, from
>  	  Mentor Graphics. It uses gcc 4.8.3, binutils 2.24.51, glibc
> @@ -98,6 +101,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_ARM201311
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_11
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
>  	help
>  	  Sourcery CodeBench toolchain for the ARM architecture, from
>  	  Mentor Graphics. It uses gcc 4.8.1, binutils 2.23.52, glibc
> @@ -126,6 +130,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_ARM201305
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_8
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_7
>  	help
>  	  Sourcery CodeBench toolchain for the ARM architecture, from
>  	  Mentor Graphics. It uses gcc 4.7.3, binutils 2.23.52, glibc
> @@ -159,6 +164,7 @@ config BR2_TOOLCHAIN_EXTERNAL_ARAGO_ARMV7A_201109
>  	select BR2_TOOLCHAIN_HAS_NATIVE_RPC
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_5
>  	# kernel headers: 2.6.31
>  	help
>  	  Texas Instruments Arago 2011.09 toolchain, with gcc 4.5.3,
> @@ -181,6 +187,7 @@ config BR2_TOOLCHAIN_EXTERNAL_ARAGO_ARMV5TE_201109
>  	select BR2_TOOLCHAIN_HAS_NATIVE_RPC
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_5
>  	# kernel headers: 2.6.31
>  	help
>  	  Texas Instruments Arago ARMv5 2011.09 toolchain, with gcc
> @@ -199,6 +206,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS201505
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_19
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_9
>  	help
>  	  Sourcery CodeBench toolchain for the MIPS architecture, from
>  	  Mentor Graphics. It uses gcc 4.9.2, binutils 2.24.51, glibc
> @@ -284,6 +292,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS201411
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_16
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_9
>  	help
>  	  Sourcery CodeBench toolchain for the MIPS architecture, from
>  	  Mentor Graphics. It uses gcc 4.9.1, binutils 2.24.51, glibc
> @@ -369,6 +378,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS201405
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_13
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
>  	help
>  	  Sourcery CodeBench toolchain for the MIPS architecture, from
>  	  Mentor Graphics. It uses gcc 4.8.3, binutils 2.24.51, glibc
> @@ -457,6 +467,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_NIOSII201405
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_12
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
>  	help
>  	  Sourcery CodeBench toolchain for the Nios-II architecture,
>  	  from Mentor Graphics. It uses gcc 4.8.3, binutils 2.24.51,
> @@ -472,6 +483,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_NIOSII201305
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_7
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_7
>  	help
>  	  Sourcery CodeBench toolchain for the Nios-II architecture,
>  	  from Mentor Graphics. It uses gcc 4.7.3, binutils 2.23.52,
> @@ -488,6 +500,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_POWERPC201203
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_2
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_6
>  	help
>  	  Sourcery CodeBench toolchain for the PowerPC architecture,
>  	  from Mentor Graphics. It uses gcc 4.6.3, binutils 2.21.53,
> @@ -505,6 +518,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_POWERPC201103
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	# kernel headers: 2.6.38
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_5
>  	help
>  	  Sourcery CodeBench toolchain for the PowerPC architecture,
>  	  from Mentor Graphics. It uses gcc 4.5.2, binutils 2.20.51,
> @@ -537,6 +551,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_POWERPC201009
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	# kernel headers: 2.6.35
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_5
>  	help
>  	  Sourcery CodeBench toolchain for the PowerPC architecture,
>  	  from Mentor Graphics. It uses gcc 4.5.1, binutils 2.20,
> @@ -569,6 +584,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_SH201209
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_5
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_7
>  	help
>  	  Sourcery CodeBench toolchain for the SuperH architecture,
>  	  from Mentor Graphics. It uses gcc 4.7.2, binutils 2.23.51,
> @@ -592,6 +608,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_SH201203
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_2
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_6
>  	help
>  	  Sourcery CodeBench toolchain for the SuperH architecture,
>  	  from Mentor Graphics. It uses gcc 4.6.3, binutils 2.21.53,
> @@ -616,6 +633,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_SH201103
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	# kernel headers: 2.6.38
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_5
>  	help
>  	  Sourcery CodeBench toolchain for the SuperH architecture,
>  	  from Mentor Graphics. It uses gcc 4.5.2, binutils 2.20,
> @@ -641,6 +659,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_AMD64_201405
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_13
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
>  	help
>  	  Sourcery CodeBench toolchain for the amd64 (x86_64)
>  	  architectures, from Mentor Graphics. It uses gcc 4.8.3,
> @@ -665,6 +684,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_X86_201209
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_5
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_7
>  	help
>  	  Sourcery CodeBench toolchain for the x86/x86_64
>  	  architectures, from Mentor Graphics. It uses gcc 4.7.2,
> @@ -692,6 +712,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_X86_201203
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_2
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_6
>  	help
>  	  Sourcery CodeBench toolchain for the x86/x86_64
>  	  architectures, from Mentor Graphics. It uses gcc 4.6.3,
> @@ -720,6 +741,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_X86_201109
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_0
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_6
>  	help
>  	  Sourcery CodeBench toolchain for the x86/x86_64
>  	  architectures, from Mentor Graphics. It uses gcc 4.6.1,
> @@ -748,6 +770,7 @@ config BR2_TOOLCHAIN_EXTERNAL_BLACKFIN_UCLINUX_2014R1
>  	select BR2_TOOLCHAIN_HAS_THREADS_DEBUG
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_10
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_3
>  	help
>  	  Toolchain for the Blackfin architecture, from
>  	  http://blackfin.uclinux.org.
> @@ -764,6 +787,7 @@ config BR2_TOOLCHAIN_EXTERNAL_BLACKFIN_UCLINUX_2013R1
>  	select BR2_TOOLCHAIN_HAS_THREADS_DEBUG
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_10
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_3
>  	help
>  	  Toolchain for the Blackfin architecture, from
>  	  http://blackfin.uclinux.org.
> @@ -780,6 +804,7 @@ config BR2_TOOLCHAIN_EXTERNAL_BLACKFIN_UCLINUX_2012R2
>  	select BR2_TOOLCHAIN_HAS_THREADS_DEBUG
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_5
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_3
>  	help
>  	  Toolchain for the Blackfin architecture, from
>  	  http://blackfin.uclinux.org.
> @@ -794,6 +819,7 @@ config BR2_TOOLCHAIN_EXTERNAL_LINARO_AARCH64
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HAS_NATIVE_RPC
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_7
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_3
>  	help
>  	  Toolchain for the AArch64 architecture, from
>  	  http://www.linaro.org/engineering/armv8/
> @@ -808,6 +834,7 @@ config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_AARCH64
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HAS_NATIVE_RPC
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_13
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
>  	help
>  	  Sourcery CodeBench toolchain for the AArch64 architecture,
>  	  from Mentor Graphics. It uses gcc 4.8.3, binutils 2.24,
> @@ -823,6 +850,7 @@ config BR2_TOOLCHAIN_EXTERNAL_MUSL_CROSS
>  	select BR2_INSTALL_LIBSTDCPP
>  	select BR2_HOSTARCH_NEEDS_IA32_LIBS
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_12
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_9
>  	help
>  	  Toolchain based on the Musl C library, provided by the
>  	  musl-cross project. It uses gcc 4.9.2, binutils 2.25 and
> @@ -849,6 +877,7 @@ config BR2_TOOLCHAIN_EXTERNAL_SYNOPSYS_ARC_2014_12
>  	select BR2_TOOLCHAIN_HAS_THREADS
>  	select BR2_TOOLCHAIN_HAS_THREADS_DEBUG
>  	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_13
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
>  	help
>  	  Toolchain for the ARC cores, from
>  	  https://github.com/foss-for-synopsys-dwc-arc-processors/toolchain/releases
> @@ -965,6 +994,47 @@ config BR2_TOOLCHAIN_EXTERNAL_MUSL
>  if BR2_TOOLCHAIN_EXTERNAL_CUSTOM
>  
>  choice
> +	bool "External toolchain gcc version"
> +	default BR2_TOOLCHAIN_EXTERNAL_GCC_4_3
> +	help
> +	  Set to the gcc version that is used by your external
> +	  toolchain.
> +
> +config BR2_TOOLCHAIN_EXTERNAL_GCC_5
> +	bool "5.x"
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_5
> +
> +config BR2_TOOLCHAIN_EXTERNAL_GCC_4_9
> +	bool "4.9.x"
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_9
> +
> +config BR2_TOOLCHAIN_EXTERNAL_GCC_4_8
> +	bool "4.8.x"
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
> +
> +config BR2_TOOLCHAIN_EXTERNAL_GCC_4_7
> +	bool "4.7.x"
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_7
> +
> +config BR2_TOOLCHAIN_EXTERNAL_GCC_4_6
> +	bool "4.6.x"
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_6
> +
> +config BR2_TOOLCHAIN_EXTERNAL_GCC_4_5
> +	bool "4.5.x"
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_5
> +
> +config BR2_TOOLCHAIN_EXTERNAL_GCC_4_4
> +	bool "4.4.x"
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_4
> +
> +config BR2_TOOLCHAIN_EXTERNAL_GCC_4_3
> +	bool "4.3.x"
> +	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_3
> +
> +endchoice
> +
> +choice
>  	bool "External toolchain kernel headers series"
>  	default BR2_TOOLCHAIN_EXTERNAL_HEADERS_REALLY_OLD
>  	help
> diff --git a/toolchain/toolchain-external/toolchain-external.mk b/toolchain/toolchain-external/toolchain-external.mk
> index 5ce4d33..3cb59c6 100644
> --- a/toolchain/toolchain-external/toolchain-external.mk
> +++ b/toolchain/toolchain-external/toolchain-external.mk
> @@ -473,6 +473,8 @@ define TOOLCHAIN_EXTERNAL_CONFIGURE_CMDS
>  	$(call check_kernel_headers_version,\
>  		$(call toolchain_find_sysroot,$(TOOLCHAIN_EXTERNAL_CC)),\
>  		$(call qstrip,$(BR2_TOOLCHAIN_HEADERS_AT_LEAST))); \
> +	$(call check_gcc_version,$(TOOLCHAIN_EXTERNAL_CC),\
> +		$(call qstrip,$(BR2_TOOLCHAIN_GCC_AT_LEAST))); \
>  	if test "$(BR2_arm)" = "y" ; then \
>  		$(call check_arm_abi,\
>  			"$(TOOLCHAIN_EXTERNAL_CC) $(TOOLCHAIN_EXTERNAL_CFLAGS)",\
> -- 
> 2.5.0
> 
> _______________________________________________
> buildroot mailing list
> buildroot@busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot
Thomas Petazzoni Aug. 5, 2015, 10:14 a.m. UTC | #2 
Dear Yann E. MORIN,

On Tue, 4 Aug 2015 21:49:48 +0200, Yann E. MORIN wrote:

> That's not true for the BR2_TOOLCHAIN_EXTERNAL_LINARO_AARCH64 toolchain:
> 
>     $ ./host/opt/ext-toolchain/bin/aarch64-linux-gnu-gcc --version
>     aarch64-linux-gnu-gcc (crosstool-NG linaro-1.13.1-4.9-2014.09 -
>     Linaro GCC 4.9-2014.09) 4.9.2 20140904 (prerelease)
> 
> Here's a better sed-expr that should match it too, as well as the other
> gcc versions; we'll make the assumption that the version string is right
> after the first closing parenthesis:
> 
>     sed -r -e '1!d; s/^[^)]+\) ([^[:space:]]+).*/\1/; s/\.[[:digit:]]+$//;'
> 
> Explanations;
> 
>   - 1!d
>       - delete if not line 1  (i.e. your 'head -n1')
> 
>   - s/^[^)]+\) ([^[:space:]]+).*/\1/
>       - eat all until the first ')' character followed by a space
>       - match as many non-space chars as possible
>       - eat all the remaining chars on the line
>       - replace by the matched expression
> 
>   - s/\.[[:digit:]]+$//
>       - eat a dot followed by as many digits as possible up to the end
>         of line
>       - replace with nothing

Thanks! I've used your regexp, and also copy/pasted your explanation
into the code. I just had to replace $ by $$ to cope with make escaping.

Thomas
Jörg Krause Aug. 8, 2015, 12:23 p.m. UTC | #3 
Dear Thomas Petazzoni, Yann Y. Marin,

On Mi, 2015-08-05 at 12:14 +0200, Thomas Petazzoni wrote:
> Dear Yann E. MORIN,
> 
> On Tue, 4 Aug 2015 21:49:48 +0200, Yann E. MORIN wrote:
> 
> > That's not true for the BR2_TOOLCHAIN_EXTERNAL_LINARO_AARCH64 
> > toolchain:
> > 
> >     $ ./host/opt/ext-toolchain/bin/aarch64-linux-gnu-gcc --version
> >     aarch64-linux-gnu-gcc (crosstool-NG linaro-1.13.1-4.9-2014.09 -
> >     Linaro GCC 4.9-2014.09) 4.9.2 20140904 (prerelease)
> > 
> > Here's a better sed-expr that should match it too, as well as the 
> > other
> > gcc versions; we'll make the assumption that the version string is 
> > right
> > after the first closing parenthesis:
> > 
> >     sed -r -e '1!d; s/^[^)]+\) ([^[:space:]]+).*/\1/; 
> > s/\.[[:digit:]]+$//;'
> > 
> > Explanations;
> > 
> >   - 1!d
> >       - delete if not line 1  (i.e. your 'head -n1')
> > 
> >   - s/^[^)]+\) ([^[:space:]]+).*/\1/
> >       - eat all until the first ')' character followed by a space
> >       - match as many non-space chars as possible
> >       - eat all the remaining chars on the line
> >       - replace by the matched expression
> > 
> >   - s/\.[[:digit:]]+$//
> >       - eat a dot followed by as many digits as possible up to the 
> > end
> >         of line
> >       - replace with nothing
> 
> Thanks! I've used your regexp, and also copy/pasted your explanation
> into the code. I just had to replace $ by $$ to cope with make 
> escaping.

This regex does not produce the version string 5 for my GCC 5.2
toolchain built with BR and included as external toolchain.

$ output/host/usr/bin/arm-linux-gcc --version
    arm-linux-gcc (Buildroot 2015.08-rc1-01365-gec8cd42) 5.2.0
    Copyright (C) 2015 Free Software Foundation, Inc.
    This is free software; see the source for copying conditions.  There
    is NO
    warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR
    PURPOSE.

$ output/host/usr/bin/arm-linux-gcc --version | sed -r -e '1!d;
s/^[^)]+\) ([^[:space:]]+).*/\1/; s/\.[[:digit:]]+$$//;'
    5.2

Best regards
Jörg Krause
Thomas Petazzoni Aug. 8, 2015, 12:33 p.m. UTC | #4 
Dear Jörg Krause,

On Sat, 08 Aug 2015 14:23:04 +0200, Jörg Krause wrote:

> > Thanks! I've used your regexp, and also copy/pasted your explanation
> > into the code. I just had to replace $ by $$ to cope with make 
> > escaping.
> 
> This regex does not produce the version string 5 for my GCC 5.2
> toolchain built with BR and included as external toolchain.
> 
> $ output/host/usr/bin/arm-linux-gcc --version
>     arm-linux-gcc (Buildroot 2015.08-rc1-01365-gec8cd42) 5.2.0
>     Copyright (C) 2015 Free Software Foundation, Inc.
>     This is free software; see the source for copying conditions.  There
>     is NO
>     warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR
>     PURPOSE.
> 
> $ output/host/usr/bin/arm-linux-gcc --version | sed -r -e '1!d;
> s/^[^)]+\) ([^[:space:]]+).*/\1/; s/\.[[:digit:]]+$$//;'
>     5.2

Hum, that's because the version number if 5.2.0, and we're removing
only one digit at the end. It's weird, because I'm pretty sure I tested
with a gcc 5.x toolchain, and I remember it was working fine. But the
version reported by gcc was 5.1, not 5.1.0.

Did maybe gcc 5.1 report 5.1, while gcc 5.2 reports 5.2.0 ?

If that's the case, then I don't see any other possibilities than
having a different case for gcc 4.x and gcc >= 5.x.

Yann ?

Thanks for the report,

Thomas
Thomas Petazzoni Aug. 12, 2015, 8:30 a.m. UTC | #5 
Dear Carlos Santos,

On Tue, 11 Aug 2015 09:19:43 -0300 (BRT), Carlos Santos wrote:

> The problem goes away if I add BR2_TOOLCHAIN_EXTERNAL_GCC_4_8=y to my
> custom defconfig. It was missing in the original file but the absence
> was harmless.
> 
> Anyone using an external toolchain will face the same problem, so I
> think it's important to emphasize the consequences of the change in
> the release notes.

There is no need for that, the error message tells you that the
selection of the gcc version is incorrect. It is exactly the same sort
of checks that is used to validate the selected C library, etc.

The mechanism to specify the gcc version has been added very recently,
so that's why you're seeing the problem now.

If you hand-edit your defconfig, you're supposed to know what you're
doing. Otherwise, 'make menuconfig' will show an option to select the
gcc version used in your external toolchain.

Best regards,

Thomas
diff mbox

Patch

diff --git a/toolchain/helpers.mk b/toolchain/helpers.mk
index 895f3f1..038939c 100644
--- a/toolchain/helpers.mk
+++ b/toolchain/helpers.mk
@@ -175,6 +175,28 @@  check_kernel_headers_version = \
 	fi
 
 #
+# Check the specific gcc version actually matches the version in the
+# toolchain
+#
+# $1: path to gcc
+# $2: expected gcc version
+#
+# The first 'sed' removes everything but the last word of the line,
+# which contains the gcc version.
+#
+# The second 'sed' removes the last digit of the version (i.e 4.9.3
+# becomes 4.9 and 5.1 becomes 5), which allows to match on the gcc
+# major version only.
+#
+check_gcc_version = \
+	expected_version="$(strip $2)" ; \
+	real_version=`$(1) --version | head -1 | sed 's%.* %%g' | sed 's%\(.*\)\.[0-9]%\1%'` ; \
+	if [ "$${real_version}" != "$${expected_version}" ] ; then \
+		echo "Incorrect selection of gcc version: expected $${expected_version}, got $${real_version}" ; \
+		exit 1 ; \
+	fi
+
+#
 # Check the availability of a particular glibc feature. This function
 # is used to check toolchain options that are always supported by
 # glibc, so we simply check that the corresponding option is properly
diff --git a/toolchain/toolchain-external/Config.in b/toolchain/toolchain-external/Config.in
index e70989e..310ea99 100644
--- a/toolchain/toolchain-external/Config.in
+++ b/toolchain/toolchain-external/Config.in
@@ -18,6 +18,7 @@  config BR2_TOOLCHAIN_EXTERNAL_LINARO_ARM
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_1
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_9
 	help
 	  Linaro toolchain for the ARM architecture. It uses Linaro
 	  GCC 2014.09 (based on gcc 4.9), Linaro GDB 2013.10 (based on
@@ -44,6 +45,7 @@  config BR2_TOOLCHAIN_EXTERNAL_LINARO_ARMEB
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_1
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_9
 	help
 	  Linaro toolchain for the ARM big endian architecture. It
 	  uses Linaro GCC 2014.09 (based on gcc 4.9), Linaro GDB
@@ -69,6 +71,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_ARM201405
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_13
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
 	help
 	  Sourcery CodeBench toolchain for the ARM architecture, from
 	  Mentor Graphics. It uses gcc 4.8.3, binutils 2.24.51, glibc
@@ -98,6 +101,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_ARM201311
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_11
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
 	help
 	  Sourcery CodeBench toolchain for the ARM architecture, from
 	  Mentor Graphics. It uses gcc 4.8.1, binutils 2.23.52, glibc
@@ -126,6 +130,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_ARM201305
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_8
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_7
 	help
 	  Sourcery CodeBench toolchain for the ARM architecture, from
 	  Mentor Graphics. It uses gcc 4.7.3, binutils 2.23.52, glibc
@@ -159,6 +164,7 @@  config BR2_TOOLCHAIN_EXTERNAL_ARAGO_ARMV7A_201109
 	select BR2_TOOLCHAIN_HAS_NATIVE_RPC
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_5
 	# kernel headers: 2.6.31
 	help
 	  Texas Instruments Arago 2011.09 toolchain, with gcc 4.5.3,
@@ -181,6 +187,7 @@  config BR2_TOOLCHAIN_EXTERNAL_ARAGO_ARMV5TE_201109
 	select BR2_TOOLCHAIN_HAS_NATIVE_RPC
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_5
 	# kernel headers: 2.6.31
 	help
 	  Texas Instruments Arago ARMv5 2011.09 toolchain, with gcc
@@ -199,6 +206,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS201505
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_19
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_9
 	help
 	  Sourcery CodeBench toolchain for the MIPS architecture, from
 	  Mentor Graphics. It uses gcc 4.9.2, binutils 2.24.51, glibc
@@ -284,6 +292,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS201411
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_16
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_9
 	help
 	  Sourcery CodeBench toolchain for the MIPS architecture, from
 	  Mentor Graphics. It uses gcc 4.9.1, binutils 2.24.51, glibc
@@ -369,6 +378,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS201405
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_13
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
 	help
 	  Sourcery CodeBench toolchain for the MIPS architecture, from
 	  Mentor Graphics. It uses gcc 4.8.3, binutils 2.24.51, glibc
@@ -457,6 +467,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_NIOSII201405
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_12
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
 	help
 	  Sourcery CodeBench toolchain for the Nios-II architecture,
 	  from Mentor Graphics. It uses gcc 4.8.3, binutils 2.24.51,
@@ -472,6 +483,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_NIOSII201305
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_7
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_7
 	help
 	  Sourcery CodeBench toolchain for the Nios-II architecture,
 	  from Mentor Graphics. It uses gcc 4.7.3, binutils 2.23.52,
@@ -488,6 +500,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_POWERPC201203
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_2
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_6
 	help
 	  Sourcery CodeBench toolchain for the PowerPC architecture,
 	  from Mentor Graphics. It uses gcc 4.6.3, binutils 2.21.53,
@@ -505,6 +518,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_POWERPC201103
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	# kernel headers: 2.6.38
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_5
 	help
 	  Sourcery CodeBench toolchain for the PowerPC architecture,
 	  from Mentor Graphics. It uses gcc 4.5.2, binutils 2.20.51,
@@ -537,6 +551,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_POWERPC201009
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	# kernel headers: 2.6.35
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_5
 	help
 	  Sourcery CodeBench toolchain for the PowerPC architecture,
 	  from Mentor Graphics. It uses gcc 4.5.1, binutils 2.20,
@@ -569,6 +584,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_SH201209
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_5
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_7
 	help
 	  Sourcery CodeBench toolchain for the SuperH architecture,
 	  from Mentor Graphics. It uses gcc 4.7.2, binutils 2.23.51,
@@ -592,6 +608,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_SH201203
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_2
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_6
 	help
 	  Sourcery CodeBench toolchain for the SuperH architecture,
 	  from Mentor Graphics. It uses gcc 4.6.3, binutils 2.21.53,
@@ -616,6 +633,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_SH201103
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	# kernel headers: 2.6.38
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_5
 	help
 	  Sourcery CodeBench toolchain for the SuperH architecture,
 	  from Mentor Graphics. It uses gcc 4.5.2, binutils 2.20,
@@ -641,6 +659,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_AMD64_201405
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_13
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
 	help
 	  Sourcery CodeBench toolchain for the amd64 (x86_64)
 	  architectures, from Mentor Graphics. It uses gcc 4.8.3,
@@ -665,6 +684,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_X86_201209
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_5
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_7
 	help
 	  Sourcery CodeBench toolchain for the x86/x86_64
 	  architectures, from Mentor Graphics. It uses gcc 4.7.2,
@@ -692,6 +712,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_X86_201203
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_2
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_6
 	help
 	  Sourcery CodeBench toolchain for the x86/x86_64
 	  architectures, from Mentor Graphics. It uses gcc 4.6.3,
@@ -720,6 +741,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_X86_201109
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_0
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_6
 	help
 	  Sourcery CodeBench toolchain for the x86/x86_64
 	  architectures, from Mentor Graphics. It uses gcc 4.6.1,
@@ -748,6 +770,7 @@  config BR2_TOOLCHAIN_EXTERNAL_BLACKFIN_UCLINUX_2014R1
 	select BR2_TOOLCHAIN_HAS_THREADS_DEBUG
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_10
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_3
 	help
 	  Toolchain for the Blackfin architecture, from
 	  http://blackfin.uclinux.org.
@@ -764,6 +787,7 @@  config BR2_TOOLCHAIN_EXTERNAL_BLACKFIN_UCLINUX_2013R1
 	select BR2_TOOLCHAIN_HAS_THREADS_DEBUG
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_10
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_3
 	help
 	  Toolchain for the Blackfin architecture, from
 	  http://blackfin.uclinux.org.
@@ -780,6 +804,7 @@  config BR2_TOOLCHAIN_EXTERNAL_BLACKFIN_UCLINUX_2012R2
 	select BR2_TOOLCHAIN_HAS_THREADS_DEBUG
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_5
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_3
 	help
 	  Toolchain for the Blackfin architecture, from
 	  http://blackfin.uclinux.org.
@@ -794,6 +819,7 @@  config BR2_TOOLCHAIN_EXTERNAL_LINARO_AARCH64
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HAS_NATIVE_RPC
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_7
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_3
 	help
 	  Toolchain for the AArch64 architecture, from
 	  http://www.linaro.org/engineering/armv8/
@@ -808,6 +834,7 @@  config BR2_TOOLCHAIN_EXTERNAL_CODESOURCERY_AARCH64
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HAS_NATIVE_RPC
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_13
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
 	help
 	  Sourcery CodeBench toolchain for the AArch64 architecture,
 	  from Mentor Graphics. It uses gcc 4.8.3, binutils 2.24,
@@ -823,6 +850,7 @@  config BR2_TOOLCHAIN_EXTERNAL_MUSL_CROSS
 	select BR2_INSTALL_LIBSTDCPP
 	select BR2_HOSTARCH_NEEDS_IA32_LIBS
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_12
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_9
 	help
 	  Toolchain based on the Musl C library, provided by the
 	  musl-cross project. It uses gcc 4.9.2, binutils 2.25 and
@@ -849,6 +877,7 @@  config BR2_TOOLCHAIN_EXTERNAL_SYNOPSYS_ARC_2014_12
 	select BR2_TOOLCHAIN_HAS_THREADS
 	select BR2_TOOLCHAIN_HAS_THREADS_DEBUG
 	select BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_13
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
 	help
 	  Toolchain for the ARC cores, from
 	  https://github.com/foss-for-synopsys-dwc-arc-processors/toolchain/releases
@@ -965,6 +994,47 @@  config BR2_TOOLCHAIN_EXTERNAL_MUSL
 if BR2_TOOLCHAIN_EXTERNAL_CUSTOM
 
 choice
+	bool "External toolchain gcc version"
+	default BR2_TOOLCHAIN_EXTERNAL_GCC_4_3
+	help
+	  Set to the gcc version that is used by your external
+	  toolchain.
+
+config BR2_TOOLCHAIN_EXTERNAL_GCC_5
+	bool "5.x"
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_5
+
+config BR2_TOOLCHAIN_EXTERNAL_GCC_4_9
+	bool "4.9.x"
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_9
+
+config BR2_TOOLCHAIN_EXTERNAL_GCC_4_8
+	bool "4.8.x"
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
+
+config BR2_TOOLCHAIN_EXTERNAL_GCC_4_7
+	bool "4.7.x"
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_7
+
+config BR2_TOOLCHAIN_EXTERNAL_GCC_4_6
+	bool "4.6.x"
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_6
+
+config BR2_TOOLCHAIN_EXTERNAL_GCC_4_5
+	bool "4.5.x"
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_5
+
+config BR2_TOOLCHAIN_EXTERNAL_GCC_4_4
+	bool "4.4.x"
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_4
+
+config BR2_TOOLCHAIN_EXTERNAL_GCC_4_3
+	bool "4.3.x"
+	select BR2_TOOLCHAIN_GCC_AT_LEAST_4_3
+
+endchoice
+
+choice
 	bool "External toolchain kernel headers series"
 	default BR2_TOOLCHAIN_EXTERNAL_HEADERS_REALLY_OLD
 	help
diff --git a/toolchain/toolchain-external/toolchain-external.mk b/toolchain/toolchain-external/toolchain-external.mk
index 5ce4d33..3cb59c6 100644
--- a/toolchain/toolchain-external/toolchain-external.mk
+++ b/toolchain/toolchain-external/toolchain-external.mk
@@ -473,6 +473,8 @@  define TOOLCHAIN_EXTERNAL_CONFIGURE_CMDS
 	$(call check_kernel_headers_version,\
 		$(call toolchain_find_sysroot,$(TOOLCHAIN_EXTERNAL_CC)),\
 		$(call qstrip,$(BR2_TOOLCHAIN_HEADERS_AT_LEAST))); \
+	$(call check_gcc_version,$(TOOLCHAIN_EXTERNAL_CC),\
+		$(call qstrip,$(BR2_TOOLCHAIN_GCC_AT_LEAST))); \
 	if test "$(BR2_arm)" = "y" ; then \
 		$(call check_arm_abi,\
 			"$(TOOLCHAIN_EXTERNAL_CC) $(TOOLCHAIN_EXTERNAL_CFLAGS)",\