Added more warning flags for GCC (as suggested in issue #28)

src/Arduino/Print.cpp

@@ -21,7 +21,7 @@ size_t Print::print(const char s[])
 size_t Print::print(double value, int digits)
 {
     char tmp[32];
-    sprintf(tmp, "%.*lg", digits+1, value);
+    sprintf(tmp, "%.*g", digits+1, value);
     return print(tmp);
 }
 

src/CMakeLists.txt

@@ -3,4 +3,32 @@ file(GLOB_RECURSE SRC_FILES *.cpp)
 
 include_directories(../include)
 
+if(CMAKE_COMPILER_IS_GNUCXX)
+	add_definitions(
+		-Wall
+		-Wcast-align
+		-Wcast-qual
+		-Wctor-dtor-privacy
+		-Wdisabled-optimization
+		-Wextra
+		-Wformat=2
+		-Winit-self
+		-Wlogical-op
+		-Wmissing-include-dirs
+		-Wno-parentheses
+		-Wno-unused
+		-Wno-variadic-macros
+		-Wnoexcept
+		-Wold-style-cast
+		-Woverloaded-virtual
+		-Wpedantic
+		-Wredundant-decls
+		-Wshadow
+		-Wsign-promo
+		-Wstrict-null-sentinel
+		-Wstrict-overflow=5
+		-Wundef
+	)
+endif()
+
 add_library(ArduinoJson ${SRC_FILES} ${INC_FILES})

src/JsonContainer.cpp

@@ -71,13 +71,13 @@ void JsonContainer::removeChild(JsonNode* childToRemove)
 
 size_t JsonContainer::size() const
 {
-    int size = 0;
+    int n = 0;
 
     for (JsonNodeIterator it = beginChildren(); it != endChildren(); ++it)
     {
-        size++;
+        n++;
     }
 
-    return size;
+    return n;
 }