From f0da50118f7bd01ed7fa97e75b790a8232d8d4dc Mon Sep 17 00:00:00 2001
From: Rahul Bedarkar <rahul.bedarkar@imgtec.com>
Date: Thu, 25 Aug 2016 17:23:38 +0530
Subject: [PATCH] add proper check for detecting header <execinfo.h>

domoticz.cpp currently assumes that on GNU/Linux systems header
<execinfo.h> is available. But that is not true. Since it provided by
C library and uClibc can be built without backtrace support. And in
such cases we get following build error.

  domoticz-3.4834/main/domoticz.cpp:48:22: fatal error: execinfo.h: No such file or directory
   #include <execinfo.h>
                        ^
  compilation terminated.

Instead of depending on __gnu_linux__, add check for detecting
presence of <execinfo.h> and guard code for dumpstack accordingly.

This build failure is detected by Buildroot autobuilder.
http://autobuild.buildroot.net/results/393/393f839e160b51ca12ac36058718ad2f0c1b50a6/

Signed-off-by: Rahul Bedarkar <rahul.bedarkar@imgtec.com>
---
 CMakeLists.txt    | 7 +++++++
 main/domoticz.cpp | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

Index: b/CMakeLists.txt
===================================================================
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -61,6 +61,13 @@
   "Where to put the executables for Domoticz"
   )
 
+INCLUDE(CheckIncludeFiles)
+CHECK_INCLUDE_FILES (execinfo.h HAVE_EXECINFO_H)
+
+IF(HAVE_EXECINFO_H)
+  ADD_DEFINITIONS(-DHAVE_EXECINFO_H)
+ENDIF(HAVE_EXECINFO_H)
+
 #set(CMAKE_EXE_LINKER_FLAGS "-static")
 
 # Macro for setting up precompiled headers. Usage:
Index: b/main/domoticz.cpp
===================================================================
--- a/main/domoticz.cpp
+++ b/main/domoticz.cpp
@@ -44,7 +44,7 @@
 	#include <string.h> 
 #endif
 
-#ifdef __gnu_linux__
+#ifdef HAVE_EXECINFO_H
 #include <execinfo.h>
 static void dumpstack(void) {
 	// Notes :