Re: [RFA] libstdc++/22203, aka PowerPC vs numeric_limits<integer>::traps

[Paolo Carlini <pcarlini at suse dot de>]

Paolo Carlini wrote:

>That would require a bit of configury, likely a new empty
>config/cpu/generic/cpu_defines.h, included by c++config.h (and therefore
>by std_limits.h), and specialized in config/cpu/powerpc/, not a big
>deal, overall.
>  
>
The below is what I tested on i686-pc-linux-gnu and
powerpc64-unknown-linux-gnu,
also checking of course that the special cpu_defines.h is selected on
powerpc.

Paolo.

///////////////////

2005-11-05  Paolo Carlini  <pcarlini@suse.de>

	PR libstdc++/22203
	* include/bits/c++config: Include cpu_defines.h.
	* include/Makefile.am: Add cpu_defines.h to host_headers.
	* configure.host: Add cpu_defines_dir.
	* configure.ac: Use it.
	* config/cpu/powerpc/cpu_defines.h: New.
	* config/cpu/generic/cpu_defines.h: Likewise.
	* configure: Regenerate.
	* Makefile.in: Likewise.
	* include/Makefile.in: Likewise.
	* libmath/Makefile.in: Likewise.
	* libsupc++/Makefile.in: Likewise.
	* po/Makefile.in: Likewise.
	* src/Makefile.in: Likewise.	
	* testsuite/Makefile.in: Likewise.

Index: include/bits/c++config
===================================================================
--- include/bits/c++config	(revision 106499)
+++ include/bits/c++config	(working copy)
@@ -34,6 +34,9 @@
 // Pick up any OS-specific definitions.
 #include <bits/os_defines.h>
 
+// Pick up any CPU-specific definitions.
+#include <bits/cpu_defines.h>
+
 // Debug mode support. Debug mode basic_string is not allowed to be
 // associated with std, because of locale and exception link
 // dependence.
Index: include/Makefile.am
===================================================================
--- include/Makefile.am	(revision 106499)
+++ include/Makefile.am	(working copy)
@@ -618,7 +618,8 @@
 	${host_srcdir}/ctype_noninline.h \
 	${host_srcdir}/os_defines.h \
 	${glibcxx_srcdir}/$(ATOMIC_WORD_SRCDIR)/atomic_word.h \
-	${glibcxx_srcdir}/$(ABI_TWEAKS_SRCDIR)/cxxabi_tweaks.h
+	${glibcxx_srcdir}/$(ABI_TWEAKS_SRCDIR)/cxxabi_tweaks.h \
+	${glibcxx_srcdir}/$(CPU_DEFINES_SRCDIR)/cpu_defines.h	
 
 # Non-installed host_header files.
 COMPATIBILITY_H = config/abi/compatibility.h
Index: configure.host
===================================================================
--- configure.host	(revision 106499)
+++ configure.host	(working copy)
@@ -39,6 +39,9 @@
 #   atomic_word_dir        location of atomic_word.h
 #                          defaults to generic.
 #
+#   cpu_defines_dir        location of cpu_defines.h
+#                          defaults to generic.
+#
 # It possibly modifies the following variables:
 #
 #   OPT_LDFLAGS            extra flags to pass when linking the library, of
@@ -64,6 +67,7 @@
 c_model=c_std
 c_compatibility=no
 atomic_word_dir=cpu/generic
+cpu_defines_dir=cpu/generic
 
 # HOST-SPECIFIC OVERRIDES
 # Set any CPU-dependent bits.
@@ -123,6 +127,14 @@
     ;;
 esac
 
+# Set specific CPU overrides for cpu_defines_dir. Most can just use generic.
+# THIS TABLE IS SORTED.  KEEP IT THAT WAY.
+case "${host_cpu}" in
+  powerpc*)
+    cpu_defines_dir=cpu/powerpc
+    ;;
+esac
+
 # Now look for the file(s) usually tied to a CPU model, and make
 # default choices for those if they haven't been explicitly set
 # already.  
Index: configure.ac
===================================================================
--- configure.ac	(revision 106499)
+++ configure.ac	(working copy)
@@ -284,10 +284,12 @@
 # Propagate the target-specific source directories through the build chain.
 ATOMICITY_SRCDIR=config/${atomicity_dir}
 ATOMIC_WORD_SRCDIR=config/${atomic_word_dir}
+CPU_DEFINES_SRCDIR=config/${cpu_defines_dir}
 OS_INC_SRCDIR=config/${os_include_dir}
 ABI_TWEAKS_SRCDIR=config/${abi_tweaks_dir}
 AC_SUBST(ATOMICITY_SRCDIR)
 AC_SUBST(ATOMIC_WORD_SRCDIR)
+AC_SUBST(CPU_DEFINES_SRCDIR)
 AC_SUBST(ABI_TWEAKS_SRCDIR)
 AC_SUBST(OS_INC_SRCDIR)
 
Index: config/cpu/powerpc/cpu_defines.h
===================================================================
--- config/cpu/powerpc/cpu_defines.h	(revision 0)
+++ config/cpu/powerpc/cpu_defines.h	(revision 0)
@@ -0,0 +1,36 @@
+// Specific definitions for generic platforms  -*- C++ -*-
+
+// Copyright (C) 2005 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+// USA.
+
+// As a special exception, you may use this file as part of a free software
+// library without restriction.  Specifically, if other files instantiate
+// templates or use macros or inline functions from this file, or you compile
+// this file and link it with other files to produce an executable, this
+// file does not by itself cause the resulting executable to be covered by
+// the GNU General Public License.  This exception does not however
+// invalidate any other reasons why the executable file might be covered by
+// the GNU General Public License.
+
+#ifndef _GLIBCXX_CPU_DEFINES
+#define _GLIBCXX_CPU_DEFINES 1
+
+// Integral divide instructions don't trap on PowerPC.
+#define __glibcxx_integral_traps false
+
+#endif
Index: config/cpu/generic/cpu_defines.h
===================================================================
--- config/cpu/generic/cpu_defines.h	(revision 0)
+++ config/cpu/generic/cpu_defines.h	(revision 0)
@@ -0,0 +1,33 @@
+// Specific definitions for generic platforms  -*- C++ -*-
+
+// Copyright (C) 2005 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+// USA.
+
+// As a special exception, you may use this file as part of a free software
+// library without restriction.  Specifically, if other files instantiate
+// templates or use macros or inline functions from this file, or you compile
+// this file and link it with other files to produce an executable, this
+// file does not by itself cause the resulting executable to be covered by
+// the GNU General Public License.  This exception does not however
+// invalidate any other reasons why the executable file might be covered by
+// the GNU General Public License.
+
+#ifndef _GLIBCXX_CPU_DEFINES
+#define _GLIBCXX_CPU_DEFINES 1
+
+#endif