fix strict aliasing issues

Patch by Przemysław Iskra (#3805)

code/qcommon/cm_trace.c

@@ -131,10 +131,7 @@ SquareRootFloat
 ================
 */
 float SquareRootFloat(float number) {
-	union {
-		float f;
-		int i;
-	} t;
+	floatint_t t;
 	float x, y;
 	const float f = 1.5F;
 

code/qcommon/msg.c

@@ -291,13 +291,9 @@ void MSG_WriteLong( msg_t *sb, int c ) {
 }
 
 void MSG_WriteFloat( msg_t *sb, float f ) {
-	union {
-		float	f;
-		int	l;
-	} dat;
-	
+	floatint_t dat;
 	dat.f = f;
-	MSG_WriteBits( sb, dat.l, 32 );
+	MSG_WriteBits( sb, dat.i, 32 );
 }
 
 void MSG_WriteString( msg_t *sb, const char *s ) {
@@ -423,13 +419,9 @@ int MSG_ReadLong( msg_t *msg ) {
 }
 
 float MSG_ReadFloat( msg_t *msg ) {
-	union {
-		byte	b[4];
-		float	f;
-		int	l;
-	} dat;
+	floatint_t dat;
 	
-	dat.l = MSG_ReadBits( msg, 32 );
+	dat.i = MSG_ReadBits( msg, 32 );
 	if ( msg->readcount > msg->cursize ) {
 		dat.f = -1;
 	}	
@@ -563,20 +555,22 @@ int	MSG_ReadDelta( msg_t *msg, int oldV, int bits ) {
 }
 
 void MSG_WriteDeltaFloat( msg_t *msg, float oldV, float newV ) {
+	floatint_t fi;
 	if ( oldV == newV ) {
 		MSG_WriteBits( msg, 0, 1 );
 		return;
 	}
+	fi.f = newV;
 	MSG_WriteBits( msg, 1, 1 );
-	MSG_WriteBits( msg, *(int *)&newV, 32 );
+	MSG_WriteBits( msg, fi.i, 32 );
 }
 
 float MSG_ReadDeltaFloat( msg_t *msg, float oldV ) {
 	if ( MSG_ReadBits( msg, 1 ) ) {
-		float	newV;
+		floatint_t fi;
 
-		*(int *)&newV = MSG_ReadBits( msg, 32 );
-		return newV;
+		fi.i = MSG_ReadBits( msg, 32 );
+		return fi.f;
 	}
 	return oldV;
 }
@@ -617,20 +611,22 @@ int	MSG_ReadDeltaKey( msg_t *msg, int key, int oldV, int bits ) {
 }
 
 void MSG_WriteDeltaKeyFloat( msg_t *msg, int key, float oldV, float newV ) {
+	floatint_t fi;
 	if ( oldV == newV ) {
 		MSG_WriteBits( msg, 0, 1 );
 		return;
 	}
+	fi.f = newV;
 	MSG_WriteBits( msg, 1, 1 );
-	MSG_WriteBits( msg, (*(int *)&newV) ^ key, 32 );
+	MSG_WriteBits( msg, fi.i ^ key, 32 );
 }
 
 float MSG_ReadDeltaKeyFloat( msg_t *msg, int key, float oldV ) {
 	if ( MSG_ReadBits( msg, 1 ) ) {
-		float	newV;
+		floatint_t fi;
 
-		*(int *)&newV = MSG_ReadBits( msg, 32 ) ^ key;
-		return newV;
+		fi.i = MSG_ReadBits( msg, 32 ) ^ key;
+		return fi.f;
 	}
 	return oldV;
 }

code/qcommon/q_math.c

@@ -501,10 +501,7 @@ void VectorRotate( vec3_t in, vec3_t matrix[3], vec3_t out )
 */
 float Q_rsqrt( float number )
 {
-	union {
-		float f;
-		int i;
-	} t;
+	floatint_t t;
 	float x2, y;
 	const float threehalfs = 1.5F;
 
@@ -519,9 +516,10 @@ float Q_rsqrt( float number )
 }
 
 float Q_fabs( float f ) {
-	int tmp = * ( int * ) &f;
-	tmp &= 0x7FFFFFFF;
-	return * ( float * ) &tmp;
+	floatint_t fi;
+	fi.f = f;
+	fi.i &= 0x7FFFFFFF;
+	return fi.f;
 }
 #endif
 
@@ -1301,15 +1299,11 @@ Don't pass doubles to this
 */
 int Q_isnan( float x )
 {
-	union
-	{
-		float f;
-		unsigned int i;
-	} t;
+	floatint_t fi;
 
-	t.f = x;
-	t.i &= 0x7FFFFFFF;
-	t.i = 0x7F800000 - t.i;
+	fi.f = x;
+	fi.ui &= 0x7FFFFFFF;
+	fi.ui = 0x7F800000 - fi.ui;
 
-	return (int)( (unsigned int)t.i >> 31 );
+	return (int)( (unsigned int)fi.ui >> 31 );
 }

code/qcommon/q_shared.c

@@ -205,16 +205,11 @@ qint64 Long64NoSwap (qint64 ll)
 	return ll;
 }
 
-typedef union {
-    float	f;
-    unsigned int i;
-} _FloatByteUnion;
-
 float FloatSwap (const float *f) {
-	_FloatByteUnion out;
+	floatint_t out;
 
 	out.f = *f;
-	out.i = LongSwap(out.i);
+	out.ui = LongSwap(out.ui);
 
 	return out.f;
 }

code/qcommon/q_shared.h

@@ -151,6 +151,12 @@ typedef unsigned char 		byte;
 
 typedef enum {qfalse, qtrue}	qboolean;
 
+typedef union {
+	float f;
+	int i;
+	unsigned int ui;
+} floatint_t;
+
 typedef int		qhandle_t;
 typedef int		sfxHandle_t;
 typedef int		fileHandle_t;

code/qcommon/qcommon.h

@@ -356,12 +356,9 @@ void	*VM_ExplicitArgPtr( vm_t *vm, intptr_t intValue );
 #define	VMA(x) VM_ArgPtr(args[x])
 static ID_INLINE float _vmf(intptr_t x)
 {
-	union {
-		int i;
-		float f;
-	} t;
-	t.i = (int)x;
-	return t.f;
+	floatint_t fi;
+	fi.i = (int) x;
+	return fi.f;
 }
 #define	VMF(x)	_vmf(args[x])