On 12/14/20 3:10 AM, Marius Hillenbrand via Gcc-patches wrote:
> Hi,
>
> Currently, when the option --enable-s390-excess-float-precision is
> omitted, configure checks the libc's behavior only for native builds yet
> defaults to the new model for cross compiles. This patch extends the
> configure-time check to cross-compiles that have target headers
> available (e.g., in the second stage when manually bootstrapping a cross
> toolchain or in the build process for cross compilers in some
> distributions).
>
> Built cross-compilers for target s390x on x86_64 and checked configure
> results and behavior wrt excess float precision (1) with target headers
> with old float_t behavior, (2) with new float_t behavior, and (3)
> without target headers.
> Bootstrapped and checked configure results on s390x.
> Tested configure and build on x86_64.
>
> Marius
>
> ----------->8------------>8------------>8------------>8------------
>
> When cross-compiling GCC with target libc headers available and
> configure option --enable-s390-excess-float-precision has been omitted,
> identify whether they clamp float_t to double or respect
> __FLT_EVAL_METHOD__ via a compile test that coerces the build-system
> compiler to use the target headers. Then derive the setting from that.
>
> gcc/ChangeLog:
>
> 2020-12-14 Marius Hillenbrand <mhil...@linux.ibm.com>
>
> * configure.ac: Change --enable-s390-excess-float-precision
> default behavior for cross compiles with target headers.
> * configure: Regenerate.
> * doc/install.texi: Adjust documentation.
OK. Make sure you commit the regenerated configury bits (and thanks for
not including them in the patch itself :-)
Jeff
