X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=build-aux%2Fwarn-on-use.h;h=c14fb274fdcd7adefd0f8df9b6909f0a77f24784;hb=ee9e39c014e2880179c91960ce1f69309d0c1500;hp=d33cfe620b02648c6b2c0a5b5cf6e0f51f84dc50;hpb=b0768fa30ba572ce15d0bd994d9ee45cda48e03b;p=gnulib.git

diff --git a/build-aux/warn-on-use.h b/build-aux/warn-on-use.h
index d33cfe620..c14fb274f 100644
--- a/build-aux/warn-on-use.h
+++ b/build-aux/warn-on-use.h
@@ -1,5 +1,5 @@
 /* A C macro for emitting warnings if a function is used.
-   Copyright (C) 2010 Free Software Foundation, Inc.
+   Copyright (C) 2010-2011 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify it
    under the terms of the GNU Lesser General Public License as published
@@ -67,10 +67,13 @@
 /* A compiler attribute is available in gcc versions 4.3.0 and later.  */
 #  define _GL_WARN_ON_USE(function, message) \
 extern __typeof__ (function) function __attribute__ ((__warning__ (message)))
-
+# elif __GNUC__ >= 3 && GNULIB_STRICT_CHECKING
+/* Verify the existence of the function.  */
+#  define _GL_WARN_ON_USE(function, message) \
+extern __typeof__ (function) function
 # else /* Unsupported.  */
 #  define _GL_WARN_ON_USE(function, message) \
-extern int _gl_warn_on_use
+_GL_WARN_EXTERN_C int _gl_warn_on_use
 # endif
 #endif
 
@@ -85,8 +88,22 @@ extern int _gl_warn_on_use
 #  define _GL_WARN_ON_USE_CXX(function,rettype,parameters_and_attributes,msg) \
 extern rettype function parameters_and_attributes \
      __attribute__ ((__warning__ (msg)))
+# elif __GNUC__ >= 3 && GNULIB_STRICT_CHECKING
+/* Verify the existence of the function.  */
+#  define _GL_WARN_ON_USE_CXX(function,rettype,parameters_and_attributes,msg) \
+extern rettype function parameters_and_attributes
 # else /* Unsupported.  */
 #  define _GL_WARN_ON_USE_CXX(function,rettype,parameters_and_attributes,msg) \
-extern int _gl_warn_on_use
+_GL_WARN_EXTERN_C int _gl_warn_on_use
+# endif
+#endif
+
+/* _GL_WARN_EXTERN_C declaration;
+   performs the declaration with C linkage.  */
+#ifndef _GL_WARN_EXTERN_C
+# if defined __cplusplus
+#  define _GL_WARN_EXTERN_C extern "C"
+# else
+#  define _GL_WARN_EXTERN_C extern
 # endif
 #endif