truncl on OSF/1 4.0

[Bruno Haible]

On OSF/1 4.0d (but not on OSF/1 5.1) the 'truncl' test fails:

  /bin/ksh: 3488 Memory fault(coredump)
  FAIL: test-truncl

The reason is that the system truncl function exists and is declared, but is
completely broken:

  $ cat foo.c
  #include <math.h>
  int main ()
  {
    truncl (0.0l);
    return 0;
  }
  $ cc foo.c -lm
  $ ./a.out 
  Segmentation fault (core dumped)

This fixes it by activating the gnulib replacement.

2008-04-13  Bruno Haible  <address@hidden>

        Make truncl work on OSF/1 4.0.
        * m4/truncl.m4 (gl_FUNC_TRUNCL): Test whether truncl actually works.
        Set REPLACE_TRUNCL, not HAVE_DECL_TRUNCL.
        * lib/math.in.h (truncl): Test REPLACE_TRUNCL, not HAVE_DECL_TRUNCL.
        * m4/math_h.m4 (gl_MATH_H_DEFAULTS): Initialize REPLACE_TRUNCL, not
        HAVE_DECL_TRUNCL.
        * modules/math (Makefile.am): Substitute REPLACE_TRUNCL, not
        HAVE_DECL_TRUNCL.
        * doc/posix-functions/truncl.texi: Document the OSF/1 4.0 problem.

*** doc/posix-functions/truncl.texi.orig        2008-04-13 20:40:47.000000000 
+0200
--- doc/posix-functions/truncl.texi     2008-04-13 20:02:00.000000000 +0200
***************
*** 11,16 ****
--- 11,19 ----
  @item
  This function is missing on some platforms:
  FreeBSD 5.2.1, NetBSD 3.0, OpenBSD 3.8, AIX 5.1, HP-UX 11, IRIX 6.5, Solaris 
9, Cygwin, Interix 3.5, BeOS.
+ @item
+ This function crashes on some platforms:
+ OSF/1 4.0.
  @end itemize
  
  Portability problems not fixed by Gnulib:
*** lib/math.in.h.orig  2008-04-13 20:40:47.000000000 +0200
--- lib/math.in.h       2008-04-13 19:59:55.000000000 +0200
***************
*** 351,357 ****
  #endif
  
  #if @GNULIB_TRUNCL@
! # if address@hidden@
  #  define truncl rpl_truncl
  extern long double truncl (long double x);
  # endif
--- 351,358 ----
  #endif
  
  #if @GNULIB_TRUNCL@
! # if @REPLACE_TRUNCL@
! #  undef truncl
  #  define truncl rpl_truncl
  extern long double truncl (long double x);
  # endif
*** m4/math_h.m4.orig   2008-04-13 20:40:47.000000000 +0200
--- m4/math_h.m4        2008-04-13 20:40:40.000000000 +0200
***************
*** 1,4 ****
! # math_h.m4 serial 11
  dnl Copyright (C) 2007-2008 Free Software Foundation, Inc.
  dnl This file is free software; the Free Software Foundation
  dnl gives unlimited permission to copy and/or distribute it,
--- 1,4 ----
! # math_h.m4 serial 12
  dnl Copyright (C) 2007-2008 Free Software Foundation, Inc.
  dnl This file is free software; the Free Software Foundation
  dnl gives unlimited permission to copy and/or distribute it,
***************
*** 74,80 ****
    HAVE_DECL_TANL=1;            AC_SUBST([HAVE_DECL_TANL])
    HAVE_DECL_TRUNC=1;           AC_SUBST([HAVE_DECL_TRUNC])
    HAVE_DECL_TRUNCF=1;          AC_SUBST([HAVE_DECL_TRUNCF])
-   HAVE_DECL_TRUNCL=1;          AC_SUBST([HAVE_DECL_TRUNCL])
    REPLACE_CEILF=0;             AC_SUBST([REPLACE_CEILF])
    REPLACE_CEILL=0;             AC_SUBST([REPLACE_CEILL])
    REPLACE_FLOORF=0;            AC_SUBST([REPLACE_FLOORF])
--- 74,79 ----
***************
*** 90,93 ****
--- 89,93 ----
    REPLACE_ROUNDL=0;            AC_SUBST([REPLACE_ROUNDL])
    REPLACE_SIGNBIT=0;           AC_SUBST([REPLACE_SIGNBIT])
    REPLACE_SIGNBIT_USING_GCC=0; AC_SUBST([REPLACE_SIGNBIT_USING_GCC])
+   REPLACE_TRUNCL=0;            AC_SUBST([REPLACE_TRUNCL])
  ])
*** m4/truncl.m4.orig   2008-04-13 20:40:47.000000000 +0200
--- m4/truncl.m4        2008-04-13 20:07:49.000000000 +0200
***************
*** 1,5 ****
! # truncl.m4 serial 1
! dnl Copyright (C) 2007 Free Software Foundation, Inc.
  dnl This file is free software; the Free Software Foundation
  dnl gives unlimited permission to copy and/or distribute it,
  dnl with or without modifications, as long as this notice is preserved.
--- 1,5 ----
! # truncl.m4 serial 2
! dnl Copyright (C) 2007-2008 Free Software Foundation, Inc.
  dnl This file is free software; the Free Software Foundation
  dnl gives unlimited permission to copy and/or distribute it,
  dnl with or without modifications, as long as this notice is preserved.
***************
*** 7,12 ****
--- 7,13 ----
  AC_DEFUN([gl_FUNC_TRUNCL],
  [
    AC_REQUIRE([gl_MATH_H_DEFAULTS])
+   AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
    dnl Persuade glibc <math.h> to declare truncl().
    AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
    dnl Test whether truncl() is declared.
***************
*** 38,48 ****
      if test "$TRUNCL_LIBM" = "?"; then
        TRUNCL_LIBM=
      fi
    else
!     HAVE_DECL_TRUNCL=0
      AC_LIBOBJ([truncl])
      TRUNCL_LIBM=
    fi
!   AC_SUBST([HAVE_DECL_TRUNCL])
    AC_SUBST([TRUNCL_LIBM])
  ])
--- 39,72 ----
      if test "$TRUNCL_LIBM" = "?"; then
        TRUNCL_LIBM=
      fi
+     dnl Test whether truncl() works. It crashes on OSF/1 4.0d.
+     AC_CACHE_CHECK([whether truncl works], [gl_cv_func_truncl_works],
+       [
+         AC_TRY_RUN([
+ #include <math.h>
+ long double x;
+ int main()
+ {
+   x = truncl (0.0L);
+   return 0;
+ }], [gl_cv_func_truncl_works=yes], [gl_cv_func_truncl_works=no],
+           [case "$host_os" in
+              osf4*) gl_cv_func_truncl_works="guessing no";;
+              *)     gl_cv_func_truncl_works="guessing yes";;
+            esac
+           ])
+       ])
+     case "$gl_cv_func_truncl_works" in
+       *yes) ;;
+       *) REPLACE_TRUNCL=1 ;;
+     esac
    else
!     REPLACE_TRUNCL=1
!   fi
!   if test $REPLACE_TRUNCL = 1; then
      AC_LIBOBJ([truncl])
      TRUNCL_LIBM=
    fi
!   AC_SUBST([REPLACE_TRUNCL])
    AC_SUBST([TRUNCL_LIBM])
  ])
*** modules/math.orig   2008-04-13 20:40:47.000000000 +0200
--- modules/math        2008-04-13 20:01:04.000000000 +0200
***************
*** 51,57 ****
              -e 's|@''HAVE_DECL_TANL''@|$(HAVE_DECL_TANL)|g' \
              -e 's|@''HAVE_DECL_TRUNC''@|$(HAVE_DECL_TRUNC)|g' \
              -e 's|@''HAVE_DECL_TRUNCF''@|$(HAVE_DECL_TRUNCF)|g' \
-             -e 's|@''HAVE_DECL_TRUNCL''@|$(HAVE_DECL_TRUNCL)|g' \
              -e 's|@''REPLACE_CEILF''@|$(REPLACE_CEILF)|g' \
              -e 's|@''REPLACE_CEILL''@|$(REPLACE_CEILL)|g' \
              -e 's|@''REPLACE_FLOORF''@|$(REPLACE_FLOORF)|g' \
--- 51,56 ----
***************
*** 67,72 ****
--- 66,72 ----
              -e 's|@''REPLACE_ROUNDL''@|$(REPLACE_ROUNDL)|g' \
              -e 's|@''REPLACE_SIGNBIT''@|$(REPLACE_SIGNBIT)|g' \
              -e 
's|@''REPLACE_SIGNBIT_USING_GCC''@|$(REPLACE_SIGNBIT_USING_GCC)|g' \
+             -e 's|@''REPLACE_TRUNCL''@|$(REPLACE_TRUNCL)|g' \
              -e '/definition of GL_LINK_WARNING/r $(LINK_WARNING_H)' \
              < $(srcdir)/math.in.h; \
        } > address@hidden