CI: Fixes for OSX + explicitely request C++11.
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index a667bd5..9611d37 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -246,7 +246,7 @@
           #include "examples/example_null/main.cpp"
 
           EOF
-          g++ -I. -Wall -Wformat -Wextra -Werror -Wno-zero-as-null-pointer-constant -Wno-double-promotion -Wno-variadic-macros -Wno-empty-body -o example_single_file example_single_file.cpp
+          g++ -I. -std=c++11 -Wall -Wformat -Wextra -Werror -Wno-zero-as-null-pointer-constant -Wno-double-promotion -Wno-variadic-macros -Wno-empty-body -o example_single_file example_single_file.cpp
 
     - name: Build example_null (freetype)
       run: |
@@ -262,7 +262,7 @@
         #include "examples/example_null/main.cpp"
 
         EOF
-        g++ -I. -Wall -Wformat -o example_single_file example_single_file.cpp
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
 
     - name: Build example_null (with ImWchar32)
       run: |
@@ -274,7 +274,7 @@
         #include "examples/example_null/main.cpp"
 
         EOF
-        g++ -I. -Wall -Wformat -o example_single_file example_single_file.cpp
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
 
     - name: Build example_null (with large ImDrawIdx + pointer ImTextureID)
       run: |
@@ -287,7 +287,7 @@
         #include "examples/example_null/main.cpp"
 
         EOF
-        g++ -I. -Wall -Wformat -o example_single_file example_single_file.cpp
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
 
     - name: Build example_null (with IMGUI_DISABLE_OBSOLETE_FUNCTIONS)
       run: |
@@ -299,7 +299,7 @@
         #include "examples/example_null/main.cpp"
 
         EOF
-        g++ -I. -Wall -Wformat -o example_single_file example_single_file.cpp
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
 
     - name: Build example_null (with IMGUI_DISABLE_OBSOLETE_KEYIO)
       run: |
@@ -311,7 +311,7 @@
         #include "examples/example_null/main.cpp"
 
         EOF
-        g++ -I. -Wall -Wformat -o example_single_file example_single_file.cpp
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
 
     - name: Build example_null (with IMGUI_DISABLE_DEMO_WINDOWS and IMGUI_DISABLE_METRICS_WINDOW)
       run: |
@@ -324,7 +324,7 @@
         #include "examples/example_null/main.cpp"
 
         EOF
-        g++ -I. -Wall -Wformat -o example_single_file example_single_file.cpp
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
 
     - name: Build example_null (with IMGUI_DISABLE_FILE_FUNCTIONS)
       run: |
@@ -336,7 +336,7 @@
         #include "examples/example_null/main.cpp"
 
         EOF
-        g++ -I. -Wall -Wformat -o example_single_file example_single_file.cpp
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
 
     - name: Build example_null (with IMGUI_USE_BGRA_PACKED_COLOR)
       run: |
@@ -348,7 +348,7 @@
         #include "examples/example_null/main.cpp"
 
         EOF
-        g++ -I. -Wall -Wformat -o example_single_file example_single_file.cpp
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
 
     - name: Build example_null (with IM_VEC2_CLASS_EXTRA and IM_VEC4_CLASS_EXTRA)
       run: |
@@ -368,7 +368,7 @@
         #include "examples/example_null/main.cpp"
 
         EOF
-        g++ -I. -Wall -Wformat -o example_single_file example_single_file.cpp
+        g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
 
     - name: Build example_null (without c++ runtime, Clang)
       run: |
@@ -380,7 +380,7 @@
         #include "examples/example_null/main.cpp"
 
         EOF
-        clang++ -I. -Wall -Wformat -nodefaultlibs -fno-rtti -fno-exceptions -fno-threadsafe-statics -lc -lm -o example_single_file example_single_file.cpp
+        clang++ -I. -std=c++11 -Wall -Wformat -nodefaultlibs -fno-rtti -fno-exceptions -fno-threadsafe-statics -lc -lm -o example_single_file example_single_file.cpp
 
     - name: Build example_glfw_opengl2
       run: make -C examples/example_glfw_opengl2
@@ -397,7 +397,7 @@
       run: make -C examples/example_sdl_opengl3
 
     - name: Build with IMGUI_IMPL_VULKAN_NO_PROTOTYPES
-      run: g++ -c -I. -DIMGUI_IMPL_VULKAN_NO_PROTOTYPES=1 backends/imgui_impl_vulkan.cpp
+      run: g++ -c -I. -std=c++11 -DIMGUI_IMPL_VULKAN_NO_PROTOTYPES=1 backends/imgui_impl_vulkan.cpp
 
   MacOS:
     runs-on: macos-latest
@@ -420,7 +420,7 @@
         #include "examples/example_null/main.cpp"
 
         EOF
-        clang++ -I. -Wall -Wformat -o example_single_file example_single_file.cpp
+        clang++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
 
     - name: Build example_null (without c++ runtime)
       run: |
@@ -431,7 +431,7 @@
         #include "examples/example_null/main.cpp"
 
         EOF
-        clang++ -I. -Wall -Wformat -nodefaultlibs -fno-rtti -fno-exceptions -fno-threadsafe-statics -lc -lm -o example_single_file example_single_file.cpp
+        clang++ -I. -std=c++11 -Wall -Wformat -nodefaultlibs -fno-rtti -fno-exceptions -fno-threadsafe-statics -lc -lm -o example_single_file example_single_file.cpp
 
     - name: Build example_glfw_opengl2
       run: make -C examples/example_glfw_opengl2
diff --git a/examples/example_glfw_metal/Makefile b/examples/example_glfw_metal/Makefile
index a174bc8..82d5ac9 100644
--- a/examples/example_glfw_metal/Makefile
+++ b/examples/example_glfw_metal/Makefile
@@ -17,7 +17,7 @@
 LIBS += -L/usr/local/lib -L/opt/homebrew/lib
 LIBS += -lglfw
 
-CXXFLAGS = -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends -I/usr/local/include -I/opt/homebrew/include
+CXXFLAGS = -std=c++11 -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends -I/usr/local/include -I/opt/homebrew/include
 CXXFLAGS += -Wall -Wformat
 CFLAGS = $(CXXFLAGS)
 
diff --git a/examples/example_glfw_opengl2/Makefile b/examples/example_glfw_opengl2/Makefile
index 5c19a27..1f15c15 100644
--- a/examples/example_glfw_opengl2/Makefile
+++ b/examples/example_glfw_opengl2/Makefile
@@ -22,7 +22,7 @@
 OBJS = $(addsuffix .o, $(basename $(notdir $(SOURCES))))
 UNAME_S := $(shell uname -s)
 
-CXXFLAGS = -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends
+CXXFLAGS = -std=c++11 -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends
 CXXFLAGS += -g -Wall -Wformat
 LIBS =
 
diff --git a/examples/example_glfw_opengl3/Makefile b/examples/example_glfw_opengl3/Makefile
index 672a705..252ce57 100644
--- a/examples/example_glfw_opengl3/Makefile
+++ b/examples/example_glfw_opengl3/Makefile
@@ -23,7 +23,7 @@
 UNAME_S := $(shell uname -s)
 LINUX_GL_LIBS = -lGL
 
-CXXFLAGS = -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends
+CXXFLAGS = -std=c++11 -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends
 CXXFLAGS += -g -Wall -Wformat
 LIBS =
 
diff --git a/examples/example_glut_opengl2/Makefile b/examples/example_glut_opengl2/Makefile
index a980f56..7af289d 100644
--- a/examples/example_glut_opengl2/Makefile
+++ b/examples/example_glut_opengl2/Makefile
@@ -17,7 +17,7 @@
 OBJS = $(addsuffix .o, $(basename $(notdir $(SOURCES))))
 UNAME_S := $(shell uname -s)
 
-CXXFLAGS = -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends
+CXXFLAGS = -std=c++11 -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends
 CXXFLAGS += -g -Wall -Wformat
 LIBS =
 
diff --git a/examples/example_null/Makefile b/examples/example_null/Makefile
index 9208e8a..9ceb353 100644
--- a/examples/example_null/Makefile
+++ b/examples/example_null/Makefile
@@ -17,7 +17,7 @@
 OBJS = $(addsuffix .o, $(basename $(notdir $(SOURCES))))
 UNAME_S := $(shell uname -s)
 
-CXXFLAGS += -I$(IMGUI_DIR)
+CXXFLAGS += -std=c++11 -I$(IMGUI_DIR)
 CXXFLAGS += -g -Wall -Wformat
 LIBS =
 
@@ -52,7 +52,7 @@
 ifeq ($(UNAME_S), Darwin) #APPLE
 	ECHO_MESSAGE = "Mac OS X"
 	ifeq ($(WITH_EXTRA_WARNINGS), 1)
-		CXXFLAGS += -Weverything -Wno-reserved-id-macro -Wno-c++98-compat-pedantic -Wno-padded -Wno-c++11-long-long -Wno-poison-system-directories
+		CXXFLAGS += -Weverything -Wno-reserved-id-macro -Wno-c++98-compat-pedantic -Wno-padded -Wno-poison-system-directories
 	endif
 	CFLAGS = $(CXXFLAGS)
 endif
diff --git a/examples/example_sdl_metal/Makefile b/examples/example_sdl_metal/Makefile
index 042bb04..2167a98 100644
--- a/examples/example_sdl_metal/Makefile
+++ b/examples/example_sdl_metal/Makefile
@@ -17,7 +17,7 @@
 LIBS += `sdl2-config --libs`
 LIBS += -L/usr/local/lib
 
-CXXFLAGS = -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends -I/usr/local/include
+CXXFLAGS = -std=c++11 -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends -I/usr/local/include
 CXXFLAGS += `sdl2-config --cflags`
 CXXFLAGS += -Wall -Wformat
 CFLAGS = $(CXXFLAGS)
diff --git a/examples/example_sdl_opengl2/Makefile b/examples/example_sdl_opengl2/Makefile
index 92e0554..24790f1 100644
--- a/examples/example_sdl_opengl2/Makefile
+++ b/examples/example_sdl_opengl2/Makefile
@@ -22,7 +22,7 @@
 OBJS = $(addsuffix .o, $(basename $(notdir $(SOURCES))))
 UNAME_S := $(shell uname -s)
 
-CXXFLAGS = -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends
+CXXFLAGS = -std=c++11 -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends
 CXXFLAGS += -g -Wall -Wformat
 LIBS =
 
diff --git a/examples/example_sdl_opengl3/Makefile b/examples/example_sdl_opengl3/Makefile
index 1b8ab42..ae22ce2 100644
--- a/examples/example_sdl_opengl3/Makefile
+++ b/examples/example_sdl_opengl3/Makefile
@@ -23,7 +23,7 @@
 UNAME_S := $(shell uname -s)
 LINUX_GL_LIBS = -lGL
 
-CXXFLAGS = -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends
+CXXFLAGS = -std=c++11 -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends
 CXXFLAGS += -g -Wall -Wformat
 LIBS =
 
diff --git a/examples/example_sdl_sdlrenderer/Makefile b/examples/example_sdl_sdlrenderer/Makefile
index 5667789..aa3b2d2 100644
--- a/examples/example_sdl_sdlrenderer/Makefile
+++ b/examples/example_sdl_sdlrenderer/Makefile
@@ -22,7 +22,7 @@
 OBJS = $(addsuffix .o, $(basename $(notdir $(SOURCES))))
 UNAME_S := $(shell uname -s)
 
-CXXFLAGS = -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends
+CXXFLAGS = -std=c++11 -I$(IMGUI_DIR) -I$(IMGUI_DIR)/backends
 CXXFLAGS += -g -Wall -Wformat
 LIBS =