3.4 PATCH: Handle C++ like ISO C94 on Tru64 UNIX

[Rainer Orth <ro at TechFak dot Uni-Bielefeld dot DE>]

For quite some time, mainline GCC fails to bootstrap on Tru64 UNIX V4.0F
and V5.1B, building libstdc++-v3:

In file included from /vol/gcc/obj/gcc-3.4-20031117/4.0f-gcc/alpha-dec-osf4.0f/libstdc++-v3/include/bits/postypes.h:46,
                 from /vol/gcc/obj/gcc-3.4-20031117/4.0f-gcc/alpha-dec-osf4.0f/libstdc++-v3/include/iosfwd:50,
                 from /vol/gcc/obj/gcc-3.4-20031117/4.0f-gcc/alpha-dec-osf4.0f/libstdc++-v3/include/bits/localefwd.h:47,
                 from /vol/gcc/obj/gcc-3.4-20031117/4.0f-gcc/alpha-dec-osf4.0f/libstdc++-v3/include/locale:44,
                 from /vol/gnu/src/gcc/gcc-dist/libstdc++-v3/src/codecvt.cc:30:
/vol/gcc/obj/gcc-3.4-20031117/4.0f-gcc/alpha-dec-osf4.0f/libstdc++-v3/include/cwchar:150: error: `::fwide' has not been declared
make[4]: *** [codecvt.lo] Error 1

This happens because the fwide declaration in <wchar.h> looks as this:

#if (__STDC_VERSION__ == 199409)
extern int      fwide __((FILE *, int));
extern wchar_t	*wcstok_r __((wchar_t *, const wchar_t *, wchar_t **));
extern size_t   __wcsftime_isoc __((wchar_t *, size_t, const wchar_t *, const struct tm *));
#define wcstok wcstok_r
#define wcsftime __wcsftime_isoc
#else
extern wchar_t	*wcstok __((wchar_t *, const wchar_t *));
extern size_t	wcsftime __((wchar_t *, size_t, const char *, const struct tm *));
#  if defined(_REENTRANT) || defined(_THREAD_SAFE)
extern wchar_t	*wcstok_r __((wchar_t *, const wchar_t *, wchar_t **));
#  endif	/* _REENTRANT || _THREAD_SAFE */
#endif /* __STDC_VERSION__ */

Bootstrap started failing when libstdc++-v3 became more lenient about wchar
requirements: the fwide test in acinclude.m4 only uses AC_CHECK_FUNCS,
which can only detect that the function exists in libc, but doesn't test if
a prototype is available at compile time.

To fix this, I define __STDC_VERSION__ to 199409L for C++ in
TARGET_OS_CPP_BUILTINS.  Unfortunately, this isn't enough, since
include/c_std/std_cwchar.h has

#undef wcsftime
#undef wcstok

effectively removing the wcsftime and wcstok declarations.  My solution is
to use fixincludes and have the wcstok/wcsftime declarations use
__asm__("wcstok_r"/"__wcsftime_isoc") to change the external names of the
functions.

This fixes the problem on Tru64 UNIX V4.0F.  The situation on V5.1B is more
difficult; I'll post a separate patch once the issues there are completely
resolved.

I still need a fix for PR bootstrap/12898 for the bootstrap to complete
successfully, e.g.

	http://gcc.gnu.org/ml/gcc-patches/2003-11/msg01598.html

With those changes, a bootstrap on alpha-dec-osf4.0f, and there are no
obvious regressions compared to the last successfull bootstrap on
20031029.

Ok for mainline?

	Rainer

-----------------------------------------------------------------------------
Rainer Orth, Faculty of Technology, Bielefeld University


Fri Nov 21 17:44:16 2003  Rainer Orth  <ro@TechFak.Uni-Bielefeld.DE>

	* config/alpha/osf.h (TARGET_OS_CPP_BUILTINS): Define
	__STDC_VERSION__ to ISO C94 for C++.

	* fixinc/inclhack.def (alpha_wchar): New fix.
	* fixinc/fixincl.x: Regenerate.
	* fixinc/tests/base/wchar.h: New file.

Index: gcc/config/alpha/osf.h
===================================================================
RCS file: /cvs/gcc/gcc/gcc/config/alpha/osf.h,v
retrieving revision 1.34
diff -u -p -r1.34 osf.h
--- gcc/config/alpha/osf.h	27 Sep 2003 04:48:12 -0000	1.34
+++ gcc/config/alpha/osf.h	21 Nov 2003 16:24:42 -0000
@@ -49,6 +49,13 @@ Boston, MA 02111-1307, USA.  */
 	   to be defined for <math.h>.  */		\
         if (LONG_DOUBLE_TYPE_SIZE == 128)		\
           builtin_define ("__X_FLOAT");			\
+							\
+	/* Tru64 UNIX V4/V5 provide several ISO C94	\
+	   features protected by the corresponding	\
+	   __STDC_VERSION__ macro.  libstdc++ v3	\
+	   needs them as well.  */			\
+	if (c_dialect_cxx ())				\
+	  builtin_define ("__STDC_VERSION__=199409L");	\
     } while (0)
 
 /* Accept DEC C flags for multithreaded programs.  We use _PTHREAD_USE_D4
Index: gcc/fixinc/inclhack.def
===================================================================
RCS file: /cvs/gcc/gcc/gcc/fixinc/inclhack.def,v
retrieving revision 1.187
diff -u -p -r1.187 inclhack.def
--- gcc/fixinc/inclhack.def	3 Nov 2003 21:07:34 -0000	1.187
+++ gcc/fixinc/inclhack.def	21 Nov 2003 16:24:48 -0000
@@ -634,6 +634,23 @@ fix = {
 
 
 /*
+ *  Change external names of wcstok/wcsftime via asm instead of macros on
+ *  Tru64 UNIX V4.0.
+ */
+fix = {
+    hackname = alpha_wchar;
+    files    = wchar.h;
+
+    mach     = "alpha*-dec-osf4*";
+    select   = "#define wcstok wcstok_r";
+    sed      = "s@#define wcstok wcstok_r@extern wchar_t *wcstok __((wchar_t *, const wchar_t *, wchar_t **)) __asm__(\"wcstok_r\");@";
+    sed      = "s@#define wcsftime __wcsftime_isoc@extern size_t   wcsftime __((wchar_t *, size_t, const wchar_t *, const struct tm *)) __asm__(\"__wcsftime_isoc\");@";
+    test_text = "#define wcstok wcstok_r\n"
+		"#define wcsftime __wcsftime_isoc";
+};
+
+
+/*
  *  For C++, avoid any typedef or macro definition of bool,
  *  and use the built in type instead.
  *  HP/UX 10.20 also has it in curses_colr/curses.h.
Index: gcc/fixinc/tests/base/wchar.h
===================================================================
RCS file: gcc/fixinc/tests/base/wchar.h
diff -N gcc/fixinc/tests/base/wchar.h
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ gcc/fixinc/tests/base/wchar.h	21 Nov 2003 16:31:38 -0000
@@ -0,0 +1,15 @@
+/*  DO NOT EDIT THIS FILE.
+
+    It has been auto-edited by fixincludes from:
+
+	"fixinc/tests/inc/wchar.h"
+
+    This had to be done to correct non-standard usages in the
+    original, manufacturer supplied header file.  */
+
+
+
+#if defined( ALPHA_WCHAR_CHECK )
+extern wchar_t *wcstok __((wchar_t *, const wchar_t *, wchar_t **)) __asm__("wcstok_r");
+extern size_t   wcsftime __((wchar_t *, size_t, const wchar_t *, const struct tm *)) __asm__("__wcsftime_isoc");
+#endif  /* ALPHA_WCHAR_CHECK */