Re: [PATCH] ArmPkg/ArmSoftFloatLib GCC4x: fix build failure

["Leif Lindholm" <leif.lindholm@linaro.org>]

On Fri, May 31, 2019 at 11:01:15PM +0200, Ard Biesheuvel wrote:
> The upstream SoftFloat code that was recently incorporated into
> ArmSoftFloatLib uses some parameterization to tweak the inlining
> and optimization behavior for different compilers.
> 
> The custom platform.h file that sets these parameters is based on
> the upstream version for Linux/ARM, but was updated to include the
> 'always_inline' GCC attribute into the INLINE macro, to ensure that
> all definitions that are marked as inline are not only inlined into
> their callers, but also to ensure that no version of the function
> is ever emitted into the object file.
> 
> This works fine on recent GCC and Clang, but the latter part turns
> out to break on GCC 4.x, resulting in duplicate definition linker
> errors. Fortunately, the synticatically more appriopriate 'static
> inline' works fine on both the recent and the older compilers, so
> let's switch to that instead.

Oh yeah, I knew that, and completely missed it when reviewing.

This behaviour hasn't actually changed substantially in later versions
of GCC. I bet all that's saving us there is LTO :)

> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: "Gao, Liming" <liming.gao@intel.com>
> Cc: "Wang, Jian J" <jian.j.wang@intel.com>
> Cc: Leif Lindholm <leif.lindholm@linaro.org>
> Cc: Michael D Kinney <michael.d.kinney@intel.com>
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>

> ---
>  ArmPkg/Library/ArmSoftFloatLib/platform.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/ArmPkg/Library/ArmSoftFloatLib/platform.h b/ArmPkg/Library/ArmSoftFloatLib/platform.h
> index 31e843463a38..07800a9d5b79 100644
> --- a/ArmPkg/Library/ArmSoftFloatLib/platform.h
> +++ b/ArmPkg/Library/ArmSoftFloatLib/platform.h
> @@ -5,7 +5,7 @@
>   */
>  
>  #define LITTLEENDIAN 1
> -#define INLINE inline __attribute__((always_inline))
> +#define INLINE static inline
>  #define SOFTFLOAT_BUILTIN_CLZ 1
>  #define SOFTFLOAT_FAST_INT64
>  #include "opts-GCC.h"
> -- 
> 2.20.1
>