Fix: specify the gcc to use on travic-ci to fix previews commit

.travis.yml

@@ -1,7 +1,17 @@
-language: python
-python: 2.7
-install: ./install.sh
+language:
+  - python
+
+python:
+  - 2.7
+
+install:
+  # g++4.8.1
+  - if [ "$CXX" = "g++" ]; then sudo apt-get install -qq g++-4.8; fi
+  - if [ "$CXX" = "g++" ]; then export CXX="g++-4.8"; fi
+  - ./install.sh
+
 script:
+  - $CXX --version
   - ./run_tests.sh
   - ./run_tests_static.sh
 

qiradb/qiradb/Trace.cpp

@@ -1,5 +1,8 @@
 #include <stdio.h>
 #include <fcntl.h>
+#ifndef __STDC_FORMAT_MACROS
+#define __STDC_FORMAT_MACROS 1
+#endif
 #include <inttypes.h>
 
 #ifndef _WIN32