[PATCH] gcc: explicitly use CFLAGS_FOR_TARGET instead of --enable-target-optspace

[Carmelo Amoroso]

Hello Alexey,
I guess you sent it to the wrong list.

You need to send to buildroot team.

Regards,
Carmelo

On 7/11/2014 6:31 PM, Alexey Brodkin wrote:
> Due to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=2222 it's impossible
> to specify custom CFLAGS_FOR_TARGET, it is always gets overriden with values
> from "config/mt-ospace":
> ===========
>   CFLAGS_FOR_TARGET = -g -Os
>   CXXFLAGS_FOR_TARGET = -g -Os
> ===========
>
> But in some situations it's required to pass custom flags on buildong of libgcc:
>   * Default flags "-g -Os" lead to build isses as with PowerPC on gcc 4.5
> (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43810)
>   * Particular CPU requires specific instructions for HW support
>   * Deep optimizations
>
> Tested by toolchain building for ARC, ARM and PowerPC with GCC 4.5
>
> Signed-off-by: Alexey Brodkin <abrodkin at synopsys.com>
>
> Cc: Anton Kolesov <akolesov at synopsys.com>
> Cc: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
> Cc: Peter Korsgaard <peter at korsgaard.com>
> Cc: Gustavo Zacarias <gustavo at zacarias.com.ar>
> ---
>   package/gcc/gcc-intermediate/gcc-intermediate.mk | 13 +++++++++++++
>   package/gcc/gcc.mk                               | 10 ----------
>   2 files changed, 13 insertions(+), 10 deletions(-)
>
> diff --git a/package/gcc/gcc-intermediate/gcc-intermediate.mk b/package/gcc/gcc-intermediate/gcc-intermediate.mk
> index db84d18..0543574 100644
> --- a/package/gcc/gcc-intermediate/gcc-intermediate.mk
> +++ b/package/gcc/gcc-intermediate/gcc-intermediate.mk
> @@ -46,4 +46,17 @@ ifeq ($(BR2_GCC_SUPPORTS_FINEGRAINEDMTUNE),y)
>   HOST_GCC_INTERMEDIATE_INSTALL_OPT += install-target-libgcc
>   endif
>
> +ifeq ($(ARCH),powerpc)
> +ifeq ($(findstring x4.5.,x$(GCC_VERSION)),x4.5.)
> +	# http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43810
> +	# Workaround until it's fixed in 4.5.4 or later
> +	HOST_GCC_INTERMEDIATE_CONF_ENV += CFLAGS_FOR_TARGET="-g -O2"
> +	HOST_GCC_INTERMEDIATE_CONF_ENV += CXXFLAGS_FOR_TARGET="-g -O2"
> +endif
> +else
> +	# Defaults are "-g -Os" from "config/mt-ospace"
> +	HOST_GCC_INTERMEDIATE_CONF_ENV += CFLAGS_FOR_TARGET="-g -Os"
> +	HOST_GCC_INTERMEDIATE_CONF_ENV += CXXFLAGS_FOR_TARGET="-g -Os"
> +endif
> +
>   $(eval $(host-autotools-package))
> diff --git a/package/gcc/gcc.mk b/package/gcc/gcc.mk
> index 5b60bc3..c6f6e41 100644
> --- a/package/gcc/gcc.mk
> +++ b/package/gcc/gcc.mk
> @@ -107,16 +107,6 @@ HOST_GCC_COMMON_CONF_OPT = \
>   HOST_GCC_COMMON_CONF_ENV = \
>   	MAKEINFO=missing
>
> -# http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43810
> -# Workaround until it's fixed in 4.5.4 or later
> -ifeq ($(ARCH),powerpc)
> -ifeq ($(findstring x4.5.,x$(GCC_VERSION)),x4.5.)
> -HOST_GCC_COMMON_CONF_OPT += --disable-target-optspace
> -endif
> -else
> -HOST_GCC_COMMON_CONF_OPT += --enable-target-optspace
> -endif
> -
>   # gcc 4.6.x quadmath requires wchar
>   ifneq ($(BR2_TOOLCHAIN_BUILDROOT_WCHAR),y)
>   HOST_GCC_COMMON_CONF_OPT += --disable-libquadmath
>