diff --git a/build/win32/vs10/gdk-win32.vcxproj b/build/win32/vs10/gdk-win32.vcxproj
index 9d0e5884d2..cf1de01656 100644
--- a/build/win32/vs10/gdk-win32.vcxproj
+++ b/build/win32/vs10/gdk-win32.vcxproj
@@ -67,7 +67,7 @@
     <ClCompile>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..\..\gdk;..\..\..\gdk\win32;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>_DEBUG;$(GdkDefines);INSIDE_GDK_WIN32;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_DEBUG;G_ENABLE_DEBUG;$(GdkDefines);INSIDE_GDK_WIN32;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <MinimalRebuild>true</MinimalRebuild>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
       <RuntimeLibrary>MultiThreadedDLL</RuntimeLibrary>
@@ -92,7 +92,7 @@
     <ClCompile>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..\..\gdk;..\..\..\gdk\win32;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>_DEBUG;$(GdkDefines);INSIDE_GDK_WIN32;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_DEBUG;G_ENABLE_DEBUG;$(GdkDefines);INSIDE_GDK_WIN32;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <MinimalRebuild>true</MinimalRebuild>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
diff --git a/build/win32/vs10/gdk.vcxprojin b/build/win32/vs10/gdk.vcxprojin
index 4029b95fdc..4116b054b7 100644
--- a/build/win32/vs10/gdk.vcxprojin
+++ b/build/win32/vs10/gdk.vcxprojin
@@ -71,7 +71,7 @@
     <ClCompile>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..\..\gdk;..\..\..\gdk\win32;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>_DEBUG;$(GdkDefines);%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_DEBUG;G_ENABLE_DEBUG;$(GdkDefines);%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <MinimalRebuild>true</MinimalRebuild>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
       <RuntimeLibrary>MultiThreadedDLL</RuntimeLibrary>
@@ -116,7 +116,7 @@
     <ClCompile>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..\..\gdk;..\..\..\gdk\win32;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>_DEBUG;$(GdkDefines);%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_DEBUG;G_ENABLE_DEBUG;$(GdkDefines);%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <MinimalRebuild>true</MinimalRebuild>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
diff --git a/build/win32/vs10/gtk-demo.vcxproj b/build/win32/vs10/gtk-demo.vcxproj
index b0b4f243d0..e4b367be4b 100644
--- a/build/win32/vs10/gtk-demo.vcxproj
+++ b/build/win32/vs10/gtk-demo.vcxproj
@@ -73,7 +73,7 @@
     <ClCompile>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..\..\gdk;..\..\..\gtk;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>_DEBUG;$(GtkPrefixDefine);%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_DEBUG;G_ENABLE_DEBUG;$(GtkPrefixDefine);%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <MinimalRebuild>true</MinimalRebuild>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
       <RuntimeLibrary>MultiThreadedDLL</RuntimeLibrary>
@@ -97,7 +97,7 @@
     <ClCompile>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..\..\gdk;..\..\..\gtk;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>_DEBUG;$(GtkPrefixDefine);%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_DEBUG;G_ENABLE_DEBUG;$(GtkPrefixDefine);%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <MinimalRebuild>true</MinimalRebuild>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
diff --git a/build/win32/vs10/gtk.vcxprojin b/build/win32/vs10/gtk.vcxprojin
index f77c8de7e0..caba55813a 100644
--- a/build/win32/vs10/gtk.vcxprojin
+++ b/build/win32/vs10/gtk.vcxprojin
@@ -71,7 +71,7 @@
     <ClCompile>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..\..\gdk;..\..\..\gtk;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>_DEBUG;$(GtkDefines);%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_DEBUG;G_ENABLE_DEBUG;$(GtkDefines);%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <MinimalRebuild>true</MinimalRebuild>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
       <RuntimeLibrary>MultiThreadedDLL</RuntimeLibrary>
@@ -116,7 +116,7 @@
     <ClCompile>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..\..\gdk;..\..\..\gdk\win32;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>_DEBUG;$(GtkDefines);%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_DEBUG;G_ENABLE_DEBUG;$(GtkDefines);%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <MinimalRebuild>true</MinimalRebuild>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
diff --git a/build/win32/vs9/gdk-win32.vcproj b/build/win32/vs9/gdk-win32.vcproj
index 2aad52b4a0..d64d1d733e 100644
--- a/build/win32/vs9/gdk-win32.vcproj
+++ b/build/win32/vs9/gdk-win32.vcproj
@@ -32,7 +32,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="..\..\..\gdk;..\..\..\gdk\win32"
-				PreprocessorDefinitions="_DEBUG;$(GdkDefines);INSIDE_GDK_WIN32"
+				PreprocessorDefinitions="_DEBUG;G_ENABLE_DEBUG;$(GdkDefines);INSIDE_GDK_WIN32"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="2"
@@ -73,7 +73,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="..\..\..\gdk;..\..\..\gdk\win32"
-				PreprocessorDefinitions="_DEBUG;$(GdkDefines);INSIDE_GDK_WIN32"
+				PreprocessorDefinitions="_DEBUG;G_ENABLE_DEBUG;$(GdkDefines);INSIDE_GDK_WIN32"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"
diff --git a/build/win32/vs9/gdk.vcprojin b/build/win32/vs9/gdk.vcprojin
index d7bafa2f60..6e9983140f 100644
--- a/build/win32/vs9/gdk.vcprojin
+++ b/build/win32/vs9/gdk.vcprojin
@@ -32,7 +32,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="..\..\..\gdk;..\..\..\gdk\win32"
-				PreprocessorDefinitions="_DEBUG;$(GdkDefines)"
+				PreprocessorDefinitions="_DEBUG;G_ENABLE_DEBUG;$(GdkDefines)"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="2"
@@ -97,7 +97,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="..\..\..\gdk;..\..\..\gdk\win32"
-				PreprocessorDefinitions="_DEBUG;$(GdkDefines)"
+				PreprocessorDefinitions="_DEBUG;G_ENABLE_DEBUG;$(GdkDefines)"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"
diff --git a/build/win32/vs9/gtk-demo.vcproj b/build/win32/vs9/gtk-demo.vcproj
index 4962a20224..4a5d55c83f 100644
--- a/build/win32/vs9/gtk-demo.vcproj
+++ b/build/win32/vs9/gtk-demo.vcproj
@@ -32,7 +32,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="..\..\..\gdk;..\..\..\gtk"
-				PreprocessorDefinitions="_DEBUG;$(GtkPrefixDefine)"
+				PreprocessorDefinitions="_DEBUG;G_ENABLE_DEBUG;$(GtkPrefixDefine)"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="2"
@@ -65,7 +65,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="..\..\..\gdk;..\..\..\gtk"
-				PreprocessorDefinitions="_DEBUG;$(GtkPrefixDefine)"
+				PreprocessorDefinitions="_DEBUG;G_ENABLE_DEBUG;$(GtkPrefixDefine)"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"
diff --git a/build/win32/vs9/gtk.vcprojin b/build/win32/vs9/gtk.vcprojin
index 6508a713aa..7aa0dca449 100644
--- a/build/win32/vs9/gtk.vcprojin
+++ b/build/win32/vs9/gtk.vcprojin
@@ -32,7 +32,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="..\..\..\gdk;..\..\..\gtk"
-				PreprocessorDefinitions="_DEBUG;$(GtkDefines)"
+				PreprocessorDefinitions="_DEBUG;G_ENABLE_DEBUG;$(GtkDefines)"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="2"
@@ -97,7 +97,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="..\..\..\gdk;..\..\..\gdk\win32"
-				PreprocessorDefinitions="_DEBUG;$(GtkDefines)"
+				PreprocessorDefinitions="_DEBUG;G_ENABLE_DEBUG;$(GtkDefines)"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"