Introduce macros CCTK_DECLARE and CCTK_DECLARE_INIT which declare or

declare and initialise local variables.  They also add the necessary
magic to prevent compiler warnings about unused variables.

If the compiler supports __attribute__((unused)), then use this.
Otherwise, use the existing fallback of taking the variable's
address.  In Fortran, use the variable's kind as fallback.

Use these macros in autogenerated code and in "cctk.h".


git-svn-id: http://svn.cactuscode.org/flesh/trunk@4146 17b73243-c579-4c4c-a9d2-2d5706c11dac

1 files changed, 25 insertions, 0 deletions

diff --git a/lib/make/aclocal.m4 b/lib/make/aclocal.m4
index a47da973..7d737582 100644
--- a/lib/make/aclocal.m4
+++ b/lib/make/aclocal.m4
@@ -330,3 +330,28 @@ if test "$cctk_cv_have_cxx_bool" = "yes" ; then
    AC_DEFINE(HAVE_CCTK_CXX_BOOL)
 fi
 ])
+
+
+
+AC_DEFUN(CCTK_C_ATTRIBUTE_UNUSED,
+[AC_CACHE_CHECK([for C __attribute__((unused))], cctk_cv_have_c_attribute_unused,
+[cctk_cv_have_c_attribute_unused=no
+AC_TRY_COMPILE(, double * foo __attribute__((unused));, cctk_cv_have_c_attribute_unused=yes, cctk_cv_have_c_attribute_unused=no)
+])
+if test "$cctk_cv_have_c_attribute_unused" = "yes" ; then
+   AC_DEFINE(HAVE_CCTK_C_ATTRIBUTE_UNUSED)
+fi
+])
+
+AC_DEFUN(CCTK_CXX_ATTRIBUTE_UNUSED,
+[AC_CACHE_CHECK([for CXX __attribute__((unused))], cctk_cv_have_cxx_attribute_unused,
+[cctk_cv_have_cxx_attribute_unused=no
+AC_LANG_SAVE
+AC_LANG_CPLUSPLUS
+AC_TRY_COMPILE(, double * foo __attribute__((unused));, cctk_cv_have_cxx_attribute_unused=yes, cctk_cv_have_cxx_attribute_unused=no)
+AC_LANG_RESTORE
+])
+if test "$cctk_cv_have_cxx_attribute_unused" = "yes" ; then
+   AC_DEFINE(HAVE_CCTK_CXX_ATTRIBUTE_UNUSED)
+fi
+])