+2021-12-21 Bruno Haible <bruno@clisp.org>
+
+ snippet/warn-on-use: Fix compilation error in C++ mode on OpenBSD 7.0.
+ * lib/warn-on-use.h (_GL_WARN_ON_USE): In C++ mode, declare function
+ with "C" linkage.
+
2021-12-21 Bruno Haible <bruno@clisp.org>
Optimize redundant 'mkdir -p .' invocations.
# if 4 < __GNUC__ || (__GNUC__ == 4 && 3 <= __GNUC_MINOR__)
/* 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)))
+_GL_WARN_EXTERN_C __typeof__ (function) function __attribute__ ((__warning__ (message)))
# define _GL_WARN_ON_USE_ATTRIBUTE(message) \
__attribute__ ((__warning__ (message)))
# elif __clang_major__ >= 4
/* Another compiler attribute is available in clang. */
# define _GL_WARN_ON_USE(function, message) \
-extern __typeof__ (function) function \
+_GL_WARN_EXTERN_C __typeof__ (function) function \
__attribute__ ((__diagnose_if__ (1, message, "warning")))
# define _GL_WARN_ON_USE_ATTRIBUTE(message) \
__attribute__ ((__diagnose_if__ (1, message, "warning")))
# elif __GNUC__ >= 3 && GNULIB_STRICT_CHECKING
/* Verify the existence of the function. */
# define _GL_WARN_ON_USE(function, message) \
-extern __typeof__ (function) function
+_GL_WARN_EXTERN_C __typeof__ (function) function
# define _GL_WARN_ON_USE_ATTRIBUTE(message)
# else /* Unsupported. */
# define _GL_WARN_ON_USE(function, message) \