Check critical static variables are initialized

In iOS the following innocent statement:

static Ogre::Radian globalVar =  Ogre::Degree( 90.0 );

can result in globalVar = 0 if static variables such as Math::PI are not
yet initialized.

This introduces very subtle bugs in iOS that are hard to detect and yet
work fine on other platforms

OgreMain/include/OgreMath.h

@@ -571,8 +571,18 @@ namespace Ogre
             return ( !useTables ) ? std::tan( fValue ) : TanTable( fValue );
         }
 
-        static inline Real DegreesToRadians( Real degrees ) { return degrees * fDeg2Rad; }
-        static inline Real RadiansToDegrees( Real radians ) { return radians * fRad2Deg; }
+        static inline Real DegreesToRadians( Real degrees )
+        {
+            OGRE_ASSERT_HIGH( fDeg2Rad != 0.0f &&
+                              "Ogre library static variables are initialized out of order" );
+            return degrees * fDeg2Rad;
+        }
+        static inline Real RadiansToDegrees( Real radians )
+        {
+            OGRE_ASSERT_HIGH( fRad2Deg != 0.0f &&
+                              "Ogre library static variables are initialized out of order" );
+            return radians * fRad2Deg;
+        }
 
         /** These functions used to set the assumed angle units (radians or degrees)
              expected when using the Angle type.

OgreMain/src/OgreMath.cpp

@@ -138,12 +138,17 @@ namespace Ogre
         }
         else
         {
+            OGRE_ASSERT_HIGH( PI != 0.0f &&
+                              "Ogre library static variables are initialized out of order" );
             return Radian( PI );
         }
     }
     //-----------------------------------------------------------------------
     Radian Math::ASin( Real fValue )
     {
+        OGRE_ASSERT_HIGH( HALF_PI != 0.0f &&
+                          "Ogre library static variables are initialized out of order" );
+
         if( -1.0 < fValue )
         {
             if( fValue < 1.0 )
@@ -193,7 +198,11 @@ namespace Ogre
     Real Math::AngleUnitsToRadians( Real angleunits )
     {
         if( msAngleUnit == AU_DEGREE )
+        {
+            OGRE_ASSERT_HIGH( fDeg2Rad != 0.0f &&
+                              "Ogre library static variables are initialized out of order" );
             return angleunits * fDeg2Rad;
+        }
         else
             return angleunits;
     }
@@ -202,7 +211,11 @@ namespace Ogre
     Real Math::RadiansToAngleUnits( Real radians )
     {
         if( msAngleUnit == AU_DEGREE )
+        {
+            OGRE_ASSERT_HIGH( fRad2Deg != 0.0f &&
+                              "Ogre library static variables are initialized out of order" );
             return radians * fRad2Deg;
+        }
         else
             return radians;
     }
@@ -211,7 +224,11 @@ namespace Ogre
     Real Math::AngleUnitsToDegrees( Real angleunits )
     {
         if( msAngleUnit == AU_RADIAN )
+        {
+            OGRE_ASSERT_HIGH( fRad2Deg != 0.0f &&
+                              "Ogre library static variables are initialized out of order" );
             return angleunits * fRad2Deg;
+        }
         else
             return angleunits;
     }
@@ -220,7 +237,11 @@ namespace Ogre
     Real Math::DegreesToAngleUnits( Real degrees )
     {
         if( msAngleUnit == AU_RADIAN )
+        {
+            OGRE_ASSERT_HIGH( fDeg2Rad != 0.0f &&
+                              "Ogre library static variables are initialized out of order" );
             return degrees * fDeg2Rad;
+        }
         else
             return degrees;
     }
@@ -955,6 +976,8 @@ namespace Ogre
     //-----------------------------------------------------------------------
     Real Math::gaussianDistribution( Real x, Real offset, Real scale )
     {
+        OGRE_ASSERT_HIGH( PI != 0.0f && "Ogre library static variables are initialized out of order" );
+
         Real nom = Math::Exp( -Math::Sqr( x - offset ) / ( 2 * Math::Sqr( scale ) ) );
         Real denom = scale * Math::Sqrt( 2 * Math::PI );