From: Shawn Routhier <sar@isc.org>
Date: Thu, 16 Feb 2012 22:07:04 +0000 (+0000)
Subject: Add a compile time check for the presence of the noreturn attribute
X-Git-Tag: v4_3_0a1~117
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e3c948003ba79f75f9bd7ae0efb5488664f44475;p=thirdparty%2Fdhcp.git

Add a compile time check for the presence of the noreturn attribute
and use it for log_fatal if it's available.  This will help code
checking programs to eliminate false positives.
[ISC-Bugs 27539]
---

diff --git a/RELNOTES b/RELNOTES
index 0fe9b7569..e0e7d604d 100644
--- a/RELNOTES
+++ b/RELNOTES
@@ -89,6 +89,11 @@ work on other platforms. Please report any problems and suggested fixes to
   support for Infiniband in the future.  This patch also corrects
   some issues we found in the socket code.  [ISC-Bugs #24245]
 
+- Add a compile time check for the presence of the noreturn attribute
+  and use it for log_fatal if it's available.  This will help code
+  checking programs to eliminate false positives.
+  [ISC-Bugs 27539]
+
 			Changes since 4.2.2
 
 - Fix the code that checks for an existing DDNS transaction to cancel
diff --git a/configure.ac b/configure.ac
index 475aefb7f..8ebedac5e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -453,6 +453,18 @@ AC_TRY_LINK(
 		   [Define to 1 if the system has 'struct if_laddrreq'.])],
 	[AC_MSG_RESULT(no)])
 
+#
+# check for GCC noreturn attribute
+#
+AC_MSG_CHECKING(for GCC noreturn attribute)
+AC_TRY_COMPILE([],[void foo() __attribute__((noreturn));],
+	[AC_MSG_RESULT(yes)
+	 AC_DEFINE([ISC_DHCP_NORETURN], [__attribute__((noreturn))],
+		   [Define to the string for a noreturn attribute.])],
+	[AC_MSG_RESULT(no)
+	 AC_DEFINE([ISC_DHCP_NORETURN], [],
+		   [Define to the string for a noreturn attribute.])])
+
 # Look for optional headers.
 AC_CHECK_HEADERS(sys/socket.h net/if_dl.h net/if6.h regex.h)
 
@@ -488,7 +500,7 @@ AC_CHECK_SIZEOF(struct iaddr *, , [
 #include <stdio.h>
 ])
 
-# Solaris does not have the msg_control or msg_controlen members in 
+# Solaris does not have the msg_control or msg_controlen members 
 # in the msghdr structure unless you define:
 #
 #   _XOPEN_SOURCE, _XOPEN_SOURCE_EXTENDED, and __EXTENSIONS__
diff --git a/includes/omapip/omapip_p.h b/includes/omapip/omapip_p.h
index 8671d4896..847f764c2 100644
--- a/includes/omapip/omapip_p.h
+++ b/includes/omapip/omapip_p.h
@@ -289,7 +289,7 @@ extern int log_perror;
 extern void (*log_cleanup) (void);
 
 void log_fatal (const char *, ...)
-	__attribute__((__format__(__printf__,1,2)));
+	__attribute__((__format__(__printf__,1,2))) ISC_DHCP_NORETURN;
 int log_error (const char *, ...)
 	__attribute__((__format__(__printf__,1,2)));
 int log_info (const char *, ...)