diff --git a/lib/framework/math_ext.h b/lib/framework/math_ext.h
index f16567b61..5e9edcf67 100644
--- a/lib/framework/math_ext.h
+++ b/lib/framework/math_ext.h
@@ -155,7 +155,7 @@ static inline void solveDifferential2ndOrder(float *y_, float *dydt_, float acce
 	y = complexDouble(*y_, 0);
 	dydt = complexDouble(*dydt_, 0);
 
-	sqd = d > 0? complexDouble(sqrt(d), 0) : complexDouble(0, sqrt(-d));                               // sqd = std::sqrt(d);
+	sqd = d > 0? complexDouble(sqrt((double)d), 0) : complexDouble(0, sqrt((double)-d));               // sqd = std::sqrt(d);
 	h1 = complexDoubleAdd(complexDouble(-friction/2, 0), sqd);                                         // h1 = -friction/2 + sqd;
 	h2 = complexDoubleSub(complexDouble(-friction/2, 0), sqd);                                         // h2 = -friction/2 - sqd;
 	e1 = complexDoubleExp(complexDoubleMul(h1, complexDouble(dt, 0)));                                 // e1 = std::exp(h1*dt);
diff --git a/lib/framework/trig.cpp b/lib/framework/trig.cpp
index 2cf481551..92656e778 100644
--- a/lib/framework/trig.cpp
+++ b/lib/framework/trig.cpp
@@ -150,7 +150,7 @@ uint16_t iAtan2(int32_t s, int32_t c)
 
 int32_t iSqrt(uint32_t n)
 {
-	uint32_t r = sqrt(n);          // Calculate square root, rounded down. Excess precision does not change the result.
+	uint32_t r = sqrt((double)n);          // Calculate square root, rounded down. Excess precision does not change the result.
 
 	// Check that we got the right result.
 	ASSERT((int32_t)(r*r - n) <= 0 && (int32_t)((r + 1)*(r + 1) - n) > 0, "Too badly broken sqrt function, iSqrt(%u) = %u.", (unsigned)n, (unsigned)r);
@@ -163,7 +163,7 @@ int32_t i64Sqrt(uint64_t n)
 	uint64_t r;
 	if (sizeof(void *) > 4)
 	{
-		r = sqrt(n);          // Calculate square root, usually rounded down. Excess precision may result in rounding down instead of up, which is fine.
+		r = sqrt((double)n);          // Calculate square root, usually rounded down. Excess precision may result in rounding down instead of up, which is fine.
 	}
 	else
 	{
diff --git a/lib/ivis_common/imdload.cpp b/lib/ivis_common/imdload.cpp
index 4dff46510..8d2fa6bec 100644
--- a/lib/ivis_common/imdload.cpp
+++ b/lib/ivis_common/imdload.cpp
@@ -425,7 +425,7 @@ static BOOL _imd_load_points( const char **ppFileData, iIMDShape *s )
 	dz = dia2.z - cen.z;
 
 	rad_sq = dx*dx + dy*dy + dz*dz;
-	rad = sqrt(rad_sq);
+	rad = sqrt((double)rad_sq);
 
 	// second pass (find tight sphere)
 	for (p = s->points; p < s->points + s->npoints; p++)
@@ -439,7 +439,7 @@ static BOOL _imd_load_points( const char **ppFileData, iIMDShape *s )
 		if (old_to_p_sq>rad_sq)
 		{
 			// this point outside current sphere
-			old_to_p = sqrt(old_to_p_sq);
+			old_to_p = sqrt((double)old_to_p_sq);
 			// radius of new sphere
 			rad = (rad + old_to_p) / 2.;
 			// rad**2 for next compare
diff --git a/src/main.cpp b/src/main.cpp
index f9dde9f7d..51cfb6100 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1123,7 +1123,7 @@ static bool fptest2(void)
 			wtf = true;
 			break;
 		}
-		b = 1/sqrt(b - (unsigned)b);
+		b = 1/sqrt((double)(b - (unsigned)b));
 	}
 	for (n = 0; n != 100; ++n)
 	{
diff --git a/src/map.cpp b/src/map.cpp
index e4a21fd41..b3be033b8 100644
--- a/src/map.cpp
+++ b/src/map.cpp
@@ -115,9 +115,6 @@ typedef struct _zonemap_save_header {
 // Maximum expected return value from get height
 #define	MAX_HEIGHT			(256 * ELEVATION_SCALE)
 
-/* Number of entries in the sqrt(1/(1+x*x)) table for aaLine */
-#define	ROOT_TABLE_SIZE		1024
-
 /* The size and contents of the map */
 SDWORD	mapWidth = 0, mapHeight = 0;
 MAPTILE	*psMapTiles = NULL;
diff --git a/src/terrain.cpp b/src/terrain.cpp
index 745bf0102..87af59fad 100644
--- a/src/terrain.cpp
+++ b/src/terrain.cpp
@@ -718,8 +718,8 @@ bool initTerrain(void)
 	debug(LOG_TERRAIN, "GL_MAX_ELEMENTS_INDICES:  %i", (int)GLmaxElementsIndices);
 	
 	// now we know these values, determine the maximum sector size achievable
-	maxSectorSizeVertices = sqrt(GLmaxElementsVertices/2)-1;
-	maxSectorSizeIndices = sqrt(GLmaxElementsIndices/12);
+	maxSectorSizeVertices = iSqrt(GLmaxElementsVertices/2)-1;
+	maxSectorSizeIndices = iSqrt(GLmaxElementsIndices/12);
 
 	debug(LOG_TERRAIN, "preferred sector size: %i", sectorSize);
 	debug(LOG_TERRAIN, "maximum sector size due to vertices: %i", maxSectorSizeVertices);