ImVector: Stricter bound-checking asserts. Fix warnings: trailing comma (old compilers), zealous preprocessor warnings.

examples/example_glfw_opengl3/main.cpp

@@ -56,7 +56,7 @@ int main(int, char**)
         return 1;
 
     // Decide GL+GLSL versions
-#if __APPLE__
+#ifdef __APPLE__
     // GL 3.2 + GLSL 150
     const char* glsl_version = "#version 150";
     glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);

examples/example_sdl_opengl3/main.cpp

@@ -48,7 +48,7 @@ int main(int, char**)
     }
 
     // Decide GL+GLSL versions
-#if __APPLE__
+#ifdef __APPLE__
     // GL 3.2 Core + GLSL 150
     const char* glsl_version = "#version 150";
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, SDL_GL_CONTEXT_FORWARD_COMPATIBLE_FLAG); // Always required on Mac