A simpler way to do the same thing.

This commit was SVN r5063.

configure.ac

@@ -975,15 +975,6 @@ AC_DEFINE_UNQUOTED(OMPI_HAVE_SA_LEN, $VALUE,
     [Whether we have the sa_len struct in <sys/socket.h> or not])
 AC_MSG_RESULT([$MSG])
 
-# IFADDR_NONE
-AC_MSG_CHECKING([for INADDR_NONE])
-AC_COMPILE_IFELSE(AC_LANG_PROGRAM([[AC_INCLUDES_DEFAULT]],
-[[unsigned long inaddr = INADDR_NONE;]]),
-[MSG=yes VALUE=1], [MSG=no VALUE=0])
-AC_DEFINE_UNQUOTED(OMPI_HAVE_INADDR_NONE, $VALUE,
-    [Whether we have INADDR_NONE constant or not])
-AC_MSG_RESULT([$MSG])
-
 # union semun in sys/sem.h
 
 # Note that sometimes we have <stdbool.h>, but it doesn't work (e.g.,

include/ompi_config_bottom.h

@@ -234,18 +234,22 @@ extern "C" {
 # define vsnprintf ompi_vsnprintf
 #endif
 
+/*
+ * Define IFADDR_NONE if we don't have it.  Solaris is the only system
+ * where I have found that it does not exist, and the man page for
+ * inet_addr() says that it returns -1 upon failure.  On Linux and
+ * other systems with IFADDR_NONE, it's just a #define to -1 anyway.
+ * So just #define it to -1 here if it doesn't already exist.
+ */
+
+#ifndef IFADDR_NONE
+#define IFADDR_NONE -1
+#endif
+
 #if defined(c_plusplus) || defined(__cplusplus)
 }
 #endif
 
-/*
- * Define __func__-preprocessor directive if the compiler does not
- * already define it.  Define it to __FILE__ so that we at least have
- * a clue where the developer is trying to indicate where the error is
- * coming from (assuming that __func__ is typically used for
- * printf-style debugging).
- */
-
 #if !HAVE_DECL___FUNC__
 #define __func__ __FILE__
 #endif

src/util/if.c

@@ -431,13 +431,7 @@ int ompi_ifaddrtoname(const char* if_addr, char* if_name, int length)
         return rc;
     }
 
-    if(
+    if(INADDR_NONE == inaddr) {
-#if OMPI_HAVE_INADDR_NONE
-       INADDR_NONE == inaddr
-#else
-       -1 == inaddr
-#endif
-       ) {
         h = gethostbyname(if_addr);
         if(0 == h) {
             ompi_output(0,"ompi_ifaddrtoname: unable to resolve %s\n", if_addr);