From 8df5d34720dd71e934545bade879e04697830757 Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Tue, 12 Dec 2017 13:56:47 +0000 Subject: Remove --with-fp / --without-fp. There is a configure option --without-fp that specifies that nofpu sysdeps directories should be used instead of fpu directories. For most glibc configurations, this option is of no use: either there is no valid nofpu variant of that configuration, or there are no fpu or nofpu sysdeps directories for that processor and so the option does nothing. For a few configurations, if you are using a soft-float compiler this option is required, and failing to use it generally results in compilation errors from inline asm using unavailable floating-point instructions. We're moving away from --with-cpu to configuring glibc based on how the compiler generates code, and it is natural to do so for --without-fp as well; in most cases the soft-float and hard-float ABIs are incompatible so you have no hope of building a working glibc with an inappropriately configured compiler or libgcc. This patch eliminates --without-fp, replacing it entirely by automatic configuration based on the compiler. Configurations for which this is relevant (coldfire / mips / powerpc32 / sh) define a variable with_fp_cond in their preconfigure fragments (under the same conditions under which those fragments do anything); this is a preprocessor conditional which the toplevel configure script then uses in a test to determine which sysdeps directories to use. The config.make with-fp variable remains. It's used only by powerpc (sysdeps/powerpc/powerpc32/Makefile) to add -mhard-float to various flags variables. For powerpc, -mcpu= options can imply use of soft-float. That could be an issue if you want to build for e.g. 476fp, but are using --with-cpu=476 because there isn't a 476fp sysdeps directory. If in future we eliminate --with-cpu and replace it entirely by testing the compiler, it would be natural at that point to eliminate that code as well (as the user should then just use a compiler defaulting to 476fp and the 476 sysdeps directory would be used automatically). Tested for x86_64, and tested with build-many-glibcs.py that installed shared libraries are unchanged by this patch. * configure.ac (--with-fp): Remove configure option. (with_fp_cond): New variable. (libc_cv_with_fp): New configure test. Use this variable instead of with_fp. * configure: Regenerated. * config.make.in (with-fp): Use @libc_cv_with_fp@. * manual/install.texi (Configuring and compiling): Remove --without-fp. * INSTALL: Regenerated. * sysdeps/m68k/preconfigure (with_fp_cond): Define for ColdFire. * sysdeps/mips/preconfigure (with_fp_cond): Define. * sysdeps/powerpc/preconfigure (with_fp_cond): Define for 32-bit. * sysdeps/sh/preconfigure (with_fp_cond): Define. * scripts/build-many-glibcs.py (Context.add_all_configs): Do not use --without-fp to configure glibc. --- manual/install.texi | 4 ---- 1 file changed, 4 deletions(-) (limited to 'manual') diff --git a/manual/install.texi b/manual/install.texi index a3cb09d..e81f1c5 100644 --- a/manual/install.texi +++ b/manual/install.texi @@ -106,10 +106,6 @@ problem and suppress these constructs, so that the library will still be usable, but functionality may be lost---for example, you can't build a shared libc with old binutils. -@item --without-fp -Use this option if your computer lacks hardware floating-point support -and your operating system does not emulate an FPU. - @c disable static doesn't work currently @c @item --disable-static @c Don't build static libraries. Static libraries aren't that useful these -- cgit v1.1