Link with -rdynamic instead of -Wl,-export-dynamic.

Recent versions of the OS X linker support this but follow the existing
OS X linker convention of using an underscore in the option name, i.e.,
-export_dynamic. Rather than changing our configure scripts to check for
that alternate spelling, it is simpler to just use the compiler's -rdynamic
option and let it deal with translating that to the appropriate linker
option. One potential disadvantage of this approach is that the compiler
will typically ignore -rdynamic on platforms where it is not supported, so
the HAVE_LINK_EXPORT_DYNAMIC in config.h will not necessarily show whether
that option has any effect or not. I don't see any in-tree uses of that
macro, so I'm assuming it is OK.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187686 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Bob Wilson 2013-08-02 22:51:06 +00:00
parent 40bacacad3
commit 244acf3a4b
6 changed files with 16 additions and 14 deletions

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@ -1239,7 +1239,7 @@ AC_LINK_GET_VERSION
dnl Determine whether the linker supports the -R option. dnl Determine whether the linker supports the -R option.
AC_LINK_USE_R AC_LINK_USE_R
dnl Determine whether the linker supports the -export-dynamic option. dnl Determine whether the compiler supports the -rdynamic option.
AC_LINK_EXPORT_DYNAMIC AC_LINK_EXPORT_DYNAMIC
dnl Determine whether the linker supports the --version-script option. dnl Determine whether the linker supports the --version-script option.
@ -1863,7 +1863,7 @@ AC_SUBST(RPATH)
dnl Determine linker rdynamic flag dnl Determine linker rdynamic flag
if test "$llvm_cv_link_use_export_dynamic" = "yes" ; then if test "$llvm_cv_link_use_export_dynamic" = "yes" ; then
RDYNAMIC="-Wl,-export-dynamic" RDYNAMIC="-rdynamic"
else else
RDYNAMIC="" RDYNAMIC=""
fi fi

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@ -40,23 +40,24 @@ if test "$llvm_cv_link_use_r" = yes ; then
]) ])
# #
# Determine if the system can handle the -R option being passed to the linker. # Determine if the system can handle the -rdynamic option being passed
# to the compiler.
# #
# This macro is specific to LLVM. # This macro is specific to LLVM.
# #
AC_DEFUN([AC_LINK_EXPORT_DYNAMIC], AC_DEFUN([AC_LINK_EXPORT_DYNAMIC],
[AC_CACHE_CHECK([for compiler -Wl,-export-dynamic option], [AC_CACHE_CHECK([for compiler -rdynamic option],
[llvm_cv_link_use_export_dynamic], [llvm_cv_link_use_export_dynamic],
[ AC_LANG_PUSH([C]) [ AC_LANG_PUSH([C])
oldcflags="$CFLAGS" oldcflags="$CFLAGS"
CFLAGS="$CFLAGS -Wl,-export-dynamic" CFLAGS="$CFLAGS -rdynamic"
AC_LINK_IFELSE([AC_LANG_PROGRAM([[]],[[]])], AC_LINK_IFELSE([AC_LANG_PROGRAM([[]],[[]])],
[llvm_cv_link_use_export_dynamic=yes],[llvm_cv_link_use_export_dynamic=no]) [llvm_cv_link_use_export_dynamic=yes],[llvm_cv_link_use_export_dynamic=no])
CFLAGS="$oldcflags" CFLAGS="$oldcflags"
AC_LANG_POP([C]) AC_LANG_POP([C])
]) ])
if test "$llvm_cv_link_use_export_dynamic" = yes ; then if test "$llvm_cv_link_use_export_dynamic" = yes ; then
AC_DEFINE([HAVE_LINK_EXPORT_DYNAMIC],[1],[Define if you can use -Wl,-export-dynamic.]) AC_DEFINE([HAVE_LINK_EXPORT_DYNAMIC],[1],[Define if you can use -rdynamic.])
fi fi
]) ])

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@ -209,7 +209,7 @@
/* Define to 1 if you have the <limits.h> header file. */ /* Define to 1 if you have the <limits.h> header file. */
#cmakedefine HAVE_LIMITS_H ${HAVE_LIMITS_H} #cmakedefine HAVE_LIMITS_H ${HAVE_LIMITS_H}
/* Define if you can use -Wl,-export-dynamic. */ /* Define if you can use -rdynamic. */
#define HAVE_LINK_EXPORT_DYNAMIC 1 #define HAVE_LINK_EXPORT_DYNAMIC 1
/* Define if you can use -Wl,-R. to pass -R. to the linker, in order to add /* Define if you can use -Wl,-R. to pass -R. to the linker, in order to add

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@ -220,7 +220,7 @@
/* Define to 1 if you have the `z' library (-lz). */ /* Define to 1 if you have the `z' library (-lz). */
#undef HAVE_LIBZ #undef HAVE_LIBZ
/* Define if you can use -Wl,-export-dynamic. */ /* Define if you can use -rdynamic. */
#undef HAVE_LINK_EXPORT_DYNAMIC #undef HAVE_LINK_EXPORT_DYNAMIC
/* Define to 1 if you have the <link.h> header file. */ /* Define to 1 if you have the <link.h> header file. */

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@ -985,7 +985,7 @@ AC_LINK_GET_VERSION
dnl Determine whether the linker supports the -R option. dnl Determine whether the linker supports the -R option.
AC_LINK_USE_R AC_LINK_USE_R
dnl Determine whether the linker supports the -export-dynamic option. dnl Determine whether the compiler supports the -rdynamic option.
AC_LINK_EXPORT_DYNAMIC AC_LINK_EXPORT_DYNAMIC
dnl Determine whether the linker supports the --version-script option. dnl Determine whether the linker supports the --version-script option.
@ -1464,7 +1464,7 @@ AC_SUBST(RPATH)
dnl Determine linker rdynamic flag dnl Determine linker rdynamic flag
if test "$llvm_cv_link_use_export_dynamic" = "yes" ; then if test "$llvm_cv_link_use_export_dynamic" = "yes" ; then
RDYNAMIC="-Wl,-export-dynamic" RDYNAMIC="-rdynamic"
else else
RDYNAMIC="" RDYNAMIC=""
fi fi

View File

@ -40,23 +40,24 @@ if test "$llvm_cv_link_use_r" = yes ; then
]) ])
# #
# Determine if the system can handle the -R option being passed to the linker. # Determine if the system can handle the -rdynamic option being passed
# to the compiler.
# #
# This macro is specific to LLVM. # This macro is specific to LLVM.
# #
AC_DEFUN([AC_LINK_EXPORT_DYNAMIC], AC_DEFUN([AC_LINK_EXPORT_DYNAMIC],
[AC_CACHE_CHECK([for compiler -Wl,-export-dynamic option], [AC_CACHE_CHECK([for compiler -rdynamic option],
[llvm_cv_link_use_export_dynamic], [llvm_cv_link_use_export_dynamic],
[ AC_LANG_PUSH([C]) [ AC_LANG_PUSH([C])
oldcflags="$CFLAGS" oldcflags="$CFLAGS"
CFLAGS="$CFLAGS -Wl,-export-dynamic" CFLAGS="$CFLAGS -rdynamic"
AC_LINK_IFELSE([AC_LANG_PROGRAM([[]],[[]])], AC_LINK_IFELSE([AC_LANG_PROGRAM([[]],[[]])],
[llvm_cv_link_use_export_dynamic=yes],[llvm_cv_link_use_export_dynamic=no]) [llvm_cv_link_use_export_dynamic=yes],[llvm_cv_link_use_export_dynamic=no])
CFLAGS="$oldcflags" CFLAGS="$oldcflags"
AC_LANG_POP([C]) AC_LANG_POP([C])
]) ])
if test "$llvm_cv_link_use_export_dynamic" = yes ; then if test "$llvm_cv_link_use_export_dynamic" = yes ; then
AC_DEFINE([HAVE_LINK_EXPORT_DYNAMIC],[1],[Define if you can use -Wl,-export-dynamic.]) AC_DEFINE([HAVE_LINK_EXPORT_DYNAMIC],[1],[Define if you can use -rdynamic.])
fi fi
]) ])