Re: [Qemu-devel] [PATCH for-4.0 v2 3/7] configure: Remove old -fno-gcse workaround for GCC 4.6.x and 4.7.[012]

[Thomas Huth]

On 2018-12-04 16:32, Thomas Huth wrote:
> Now that we require at least GCC 4.8, we don't need this als workaround
> for 4.6 and 4.7 anymore.
> 
> Reviewed-by: Richard Henderson <address@hidden>
> Signed-off-by: Thomas Huth <address@hidden>
> ---
>  Makefile.target |  3 ---
>  configure       | 27 ---------------------------
>  2 files changed, 30 deletions(-)
> 
> diff --git a/Makefile.target b/Makefile.target
> index 4d56298..44ec4b6 100644
> --- a/Makefile.target
> +++ b/Makefile.target
> @@ -158,9 +158,6 @@ GENERATED_FILES += hmp-commands.h hmp-commands-info.h
>  
>  endif # CONFIG_SOFTMMU
>  
> -# Workaround for http://gcc.gnu.org/PR55489, see configure.
> -%/translate.o: QEMU_CFLAGS += $(TRANSLATE_OPT_CFLAGS)
> -
>  dummy := $(call unnest-vars,,obj-y)
>  all-obj-y := $(obj-y)
>  
> diff --git a/configure b/configure
> index ca364f6..c160b59 100755
> --- a/configure
> +++ b/configure
> @@ -1936,32 +1936,6 @@ else
>    QEMU_CFLAGS="$QEMU_CFLAGS -Wno-missing-braces"
>  fi
>  
> -# Workaround for http://gcc.gnu.org/PR55489.  Happens with -fPIE/-fPIC and
> -# large functions that use global variables.  The bug is in all releases of
> -# GCC, but it became particularly acute in 4.6.x and 4.7.x.  It is fixed in
> -# 4.7.3 and 4.8.0.  We should be able to delete this at the end of 2013.
> -cat > $TMPC << EOF
> -#if __GNUC__ == 4 && (__GNUC_MINOR__ == 6 || (__GNUC_MINOR__ == 7 && 
> __GNUC_PATCHLEVEL__ <= 2))
> -int main(void) { return 0; }
> -#else
> -#error No bug in this compiler.
> -#endif
> -EOF
> -if compile_prog "-Werror -fno-gcse" "" ; then
> -  TRANSLATE_OPT_CFLAGS=-fno-gcse
> -fi
> -
> -if test "$static" = "yes" ; then
> -  if test "$modules" = "yes" ; then
> -    error_exit "static and modules are mutually incompatible"
> -  fi
> -  if test "$pie" = "yes" ; then
> -    error_exit "static and pie are mutually incompatible"
> -  else
> -    pie="no"
> -  fi
> -fi

For the records: I just noticed that the last 10 lines do not belong to
the gcse workaround - I'll remove them from the patch again.

 Thomas