diff --git a/src/c_console.cpp b/src/c_console.cpp
index 0868612292..2d164c4787 100644
--- a/src/c_console.cpp
+++ b/src/c_console.cpp
@@ -1747,6 +1747,14 @@ void C_AddTabCommand (const char *name)
 
 void C_RemoveTabCommand (const char *name)
 {
+	if (TabCommands.Size() == 0)
+	{
+		// There are no tab commands that can be removed.
+		// This is important to skip construction of aname 
+		// in case the NameManager has already been destroyed.
+		return;
+	}
+
 	FName aname(name, true);
 
 	if (aname == NAME_None)
diff --git a/src/gl/data/gl_matrix.cpp b/src/gl/data/gl_matrix.cpp
index bc0f4129f9..d8017ad404 100644
--- a/src/gl/data/gl_matrix.cpp
+++ b/src/gl/data/gl_matrix.cpp
@@ -422,7 +422,7 @@ void
 VSMatrix::computeNormalMatrix(const FLOATTYPE *aMatrix) 
 {
 
-	FLOATTYPE mMat3x3[9];
+	double mMat3x3[9];
 
 	mMat3x3[0] = aMatrix[0];
 	mMat3x3[1] = aMatrix[1];
@@ -436,7 +436,7 @@ VSMatrix::computeNormalMatrix(const FLOATTYPE *aMatrix)
 	mMat3x3[7] = aMatrix[9];
 	mMat3x3[8] = aMatrix[10];
 
-	FLOATTYPE det, invDet;
+	double det, invDet;
 
 	det = mMat3x3[0] * (mMat3x3[4] * mMat3x3[8] - mMat3x3[5] * mMat3x3[7]) +
 		  mMat3x3[1] * (mMat3x3[5] * mMat3x3[6] - mMat3x3[8] * mMat3x3[3]) +
diff --git a/src/gl/scene/gl_sprite.cpp b/src/gl/scene/gl_sprite.cpp
index 36e3e00ffc..4a94cdb9c0 100644
--- a/src/gl/scene/gl_sprite.cpp
+++ b/src/gl/scene/gl_sprite.cpp
@@ -375,7 +375,7 @@ void GLSprite::Draw(int pass)
 			gl_RenderState.Apply();
 
 			FVector3 v[4];
-			if ((actor->renderflags & RF_SPRITETYPEMASK) == RF_FLATSPRITE)
+			if (actor != nullptr && (actor->renderflags & RF_SPRITETYPEMASK) == RF_FLATSPRITE)
 			{
 			}
 			else
@@ -437,7 +437,7 @@ inline void GLSprite::PutSprite(bool translucent)
 {
 	int list;
 	// [BB] Allow models to be drawn in the GLDL_TRANSLUCENT pass.
-	if (translucent || (!modelframe && (actor->renderflags & RF_SPRITETYPEMASK) != RF_WALLSPRITE))
+	if (translucent || actor == nullptr || (!modelframe && (actor->renderflags & RF_SPRITETYPEMASK) != RF_WALLSPRITE))
 	{
 		list = GLDL_TRANSLUCENT;
 	}
diff --git a/src/gl/system/gl_framebuffer.cpp b/src/gl/system/gl_framebuffer.cpp
index ed0d07bd56..d99566a5a3 100644
--- a/src/gl/system/gl_framebuffer.cpp
+++ b/src/gl/system/gl_framebuffer.cpp
@@ -197,7 +197,7 @@ void OpenGLFrameBuffer::Update()
 	Unlock();
 	CheckBench();
 
-	if (Windowed)
+	if (!IsFullscreen())
 	{
 		int clientWidth = GetClientWidth();
 		int clientHeight = GetClientHeight();
diff --git a/src/name.cpp b/src/name.cpp
index 8140829c68..ecedcf0f31 100644
--- a/src/name.cpp
+++ b/src/name.cpp
@@ -35,6 +35,7 @@
 #include <string.h>
 #include "name.h"
 #include "c_dispatch.h"
+#include "c_console.h"
 
 // MACROS ------------------------------------------------------------------
 
@@ -268,6 +269,8 @@ FName::NameManager::~NameManager()
 {
 	NameBlock *block, *next;
 
+	C_ClearTabCommands();
+
 	for (block = Blocks; block != NULL; block = next)
 	{
 		next = block->NextBlock;