CI: Enable extended warnings in example_null builds.

CI: Add MinGW build with extra warnings on windows.

(cherry picked from commit ebc98c273054d0f9b305a1346db98052616a8b21)

.github/workflows/build.yml

@@ -41,6 +41,9 @@ jobs:
           }
 
       # Not using matrix here because it would inflate job count too much. Check out and setup is done for every job and that makes build times way too long.
+      - name: Build example_null (extra warnings)
+        run: mingw32-make -C examples/example_null EXTRA_WARNINGS=1
+
       - name: Build Win32 example_glfw_opengl2
         shell: cmd
         run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_glfw_opengl2/example_glfw_opengl2.vcxproj /p:Platform=Win32 /p:Configuration=Release'
@@ -150,8 +153,8 @@ jobs:
         sudo apt-get update
         sudo apt-get install -y libglfw3-dev libsdl2-dev
 
-    - name: Build example_null
-      run: make -C examples/example_null
+    - name: Build example_null (extra warnings)
+      run: make -C examples/example_null EXTRA_WARNINGS=1
 
     - name: Build example_glfw_opengl2
       run: make -C examples/example_glfw_opengl2
@@ -179,8 +182,8 @@ jobs:
         brew install glfw3
         brew install sdl2
 
-    - name: Build example_null
-      run: make -C examples/example_null
+    - name: Build example_null (extra warnings)
+      run: make -C examples/example_null EXTRA_WARNINGS=1
 
     - name: Build example_glfw_opengl2
       run: make -C examples/example_glfw_opengl2

examples/example_null/Makefile

@@ -8,27 +8,42 @@ SOURCES = main.cpp
 SOURCES += ../../imgui.cpp ../../imgui_demo.cpp ../../imgui_draw.cpp ../../imgui_widgets.cpp
 OBJS = $(addsuffix .o, $(basename $(notdir $(SOURCES))))
 UNAME_S := $(shell uname -s)
+EXTRA_WARNINGS ?= 0
 
 CXXFLAGS = -I../ -I../../
 CXXFLAGS += -g -Wall -Wformat
 LIBS =
 
+# We use the EXTRA_WARNINGS flag on our CI setup to eagerly catch zealous warnings
+ifeq ($(EXTRA_WARNINGS), 1)
+	CXXFLAGS += -Wno-zero-as-null-pointer-constant -Wno-double-promotion -Wno-variadic-macros
+endif
+
 ##---------------------------------------------------------------------
 ## BUILD FLAGS PER PLATFORM
 ##---------------------------------------------------------------------
 
 ifeq ($(UNAME_S), Linux) #LINUX
 	ECHO_MESSAGE = "Linux"
+	ifneq ($(EXTRA_WARNINGS), 0)
+		CXXFLAGS += -Wextra -pedantic
+	endif
 	CFLAGS = $(CXXFLAGS)
 endif
 
 ifeq ($(UNAME_S), Darwin) #APPLE
 	ECHO_MESSAGE = "Mac OS X"
+	ifneq ($(EXTRA_WARNINGS), 0)
+		CXXFLAGS += -Weverything -Wno-reserved-id-macro -Wno-c++98-compat-pedantic -Wno-padded -Wno-c++11-long-long
+	endif
 	CFLAGS = $(CXXFLAGS)
 endif
 
 ifeq ($(findstring MINGW,$(UNAME_S)),MINGW)
 	ECHO_MESSAGE = "MinGW"
+	ifneq ($(EXTRA_WARNINGS), 0)
+		CXXFLAGS += -Wextra -pedantic
+	endif
 	CFLAGS = $(CXXFLAGS)
 endif