diff --git a/README.md b/README.md
index 4a4ae003..1a154d4a 100644
--- a/README.md
+++ b/README.md
@@ -70,7 +70,7 @@ Run 'bspguy <command> help' to read about a specific command.
 
 ### Linux users:
 1. Install Git, CMake, X11, GLFW, GLEW, and a compiler.
-    * Debian: `sudo apt install build-essential git cmake libx11-dev libxrandr-dev libxinerama-dev libxcursor-dev libxi-dev libgl1-mesa-dev xorg-dev libglfw3-dev libglew-dev`
+    * Debian: `sudo apt install build-essential git cmake libx11-dev libxrandr-dev libxinerama-dev libxcursor-dev libxi-dev libgl1-mesa-dev xorg-dev libglfw3-dev libglew-dev libxxf86vm-dev`
 1. Open a terminal somewhere and run these commands:
     ```
     git clone --recurse-submodules https://github.com/wootguy/bspguy
diff --git a/src/bsp/Bsp.cpp b/src/bsp/Bsp.cpp
index 619458d6..8b8640dc 100644
--- a/src/bsp/Bsp.cpp
+++ b/src/bsp/Bsp.cpp
@@ -11,6 +11,7 @@
 #include <fstream>
 #include <algorithm>
 #include "Clipper.h"
+#include <float.h>
 
 
 typedef map< string, vec3 > mapStringToVector;
@@ -5587,4 +5588,4 @@ void Bsp::append_lump(int lumpIdx, void* newData, int appendLength) {
 	memcpy(newLump + oldLen, newData, appendLength);
 
 	replace_lump(lumpIdx, newLump, oldLen + appendLength);
-}
\ No newline at end of file
+}
diff --git a/src/bsp/BspMerger.cpp b/src/bsp/BspMerger.cpp
index 0626a875..431da1d9 100644
--- a/src/bsp/BspMerger.cpp
+++ b/src/bsp/BspMerger.cpp
@@ -5,6 +5,7 @@
 #include "Wad.h"
 #include <fstream>
 #include "globals.h"
+#include <algorithm>
 
 BspMerger::BspMerger() {
 
diff --git a/src/bsp/Entity.cpp b/src/bsp/Entity.cpp
index 657aedc2..a75b663e 100644
--- a/src/bsp/Entity.cpp
+++ b/src/bsp/Entity.cpp
@@ -1,6 +1,7 @@
 #include "Entity.h"
 #include "util.h"
 #include <set>
+#include <algorithm>
 
 using namespace std;
 
@@ -491,4 +492,4 @@ bool Entity::isEverVisible() {
 	}
 
 	return true;
-}
\ No newline at end of file
+}
diff --git a/src/bsp/NavMesh.cpp b/src/bsp/NavMesh.cpp
index 5d58448e..26493c8f 100644
--- a/src/bsp/NavMesh.cpp
+++ b/src/bsp/NavMesh.cpp
@@ -3,6 +3,7 @@
 #include "PolyOctree.h"
 #include "Clipper.h"
 #include "util.h"
+#include <string.h>
 
 bool NavNode::addLink(int node, int srcEdge, int dstEdge, int16_t zDist, uint8_t flags) {
 	if (srcEdge < 0 || srcEdge >= MAX_NAV_POLY_VERTS) {
@@ -136,7 +137,8 @@ void NavMesh::getLinkMidPoints(int iNode, int iLink, vec3& srcMid, vec3& dstMid)
 	vec2 e4 = dstPoly.topdownVerts[e4i];
 
 	float t0, t1, t2, t3;
-	float overlapDist = Line2D(e1, e2).getOverlapRanges(Line2D(e3, e4), t0, t1, t2, t3);
+	Line2D e34(e3, e4);
+	float overlapDist = Line2D(e1, e2).getOverlapRanges(e34, t0, t1, t2, t3);
 
 	{
 		vec3 edgeStart = srcPoly.verts[link.srcEdge];
diff --git a/src/bsp/NavMeshGenerator.cpp b/src/bsp/NavMeshGenerator.cpp
index 3ee0e984..c7cfea03 100644
--- a/src/bsp/NavMeshGenerator.cpp
+++ b/src/bsp/NavMeshGenerator.cpp
@@ -7,6 +7,7 @@
 #include <set>
 #include "util.h"
 #include "PolyOctree.h"
+#include <algorithm>
 
 NavMesh* NavMeshGenerator::generate(Bsp* map, int hull) {
 	float NavMeshGeneratorGenStart = glfwGetTime();
@@ -463,4 +464,4 @@ int NavMeshGenerator::tryEdgeLinkPolys(Bsp* map, NavMesh* mesh, int srcPolyIdx,
 	}
 
 	return 0;
-}
\ No newline at end of file
+}
diff --git a/src/editor/BspRenderer.cpp b/src/editor/BspRenderer.cpp
index 418114e7..a22e103f 100644
--- a/src/editor/BspRenderer.cpp
+++ b/src/editor/BspRenderer.cpp
@@ -20,6 +20,7 @@
 #include <iomanip>
 #include <set>
 #include <fstream>
+#include <algorithm>
 
 #include "icons/missing.h"
 
diff --git a/src/editor/Gui.cpp b/src/editor/Gui.cpp
index 025cd14b..1b75d61a 100644
--- a/src/editor/Gui.cpp
+++ b/src/editor/Gui.cpp
@@ -13,6 +13,7 @@
 #include <fstream>
 #include <set>
 #include "tinyfiledialogs.h"
+#include <algorithm>
 
 // embedded binary data
 #include "fonts/robotomono.h"
@@ -4360,4 +4361,4 @@ void Gui::checkFaceErrors() {
 void Gui::refresh() {
 	reloadLimits();
 	checkValidHulls();
-}
\ No newline at end of file
+}
diff --git a/src/editor/LightmapNode.cpp b/src/editor/LightmapNode.cpp
index eb5327c5..b920d6b8 100644
--- a/src/editor/LightmapNode.cpp
+++ b/src/editor/LightmapNode.cpp
@@ -1,5 +1,6 @@
 #include "LightmapNode.h"
 #include <stdint.h>
+#include <string.h>
 
 LightmapNode::LightmapNode( int offX, int offY, int mapW, int mapH )
 {
diff --git a/src/editor/Renderer.cpp b/src/editor/Renderer.cpp
index a2f03d61..8721497a 100644
--- a/src/editor/Renderer.cpp
+++ b/src/editor/Renderer.cpp
@@ -14,6 +14,7 @@
 #include <fstream>
 #include "globals.h"
 #include "NavMesh.h"
+#include <algorithm>
 
 // everything except VIS, ENTITIES, MARKSURFS
 #define EDIT_MODEL_LUMPS (PLANES | TEXTURES | VERTICES | NODES | TEXINFO | FACES | LIGHTING | CLIPNODES | LEAVES | EDGES | SURFEDGES | MODELS)
diff --git a/src/qtools/vis.cpp b/src/qtools/vis.cpp
index e573bb3c..4ad483f4 100644
--- a/src/qtools/vis.cpp
+++ b/src/qtools/vis.cpp
@@ -2,6 +2,7 @@
 #include "rad.h"
 #include "util.h"
 #include "globals.h"
+#include <string.h>
 
 #define MAX_MAP_LEAVES 65536 // set this to the largest value in any engine
 
diff --git a/src/util/PolyOctree.cpp b/src/util/PolyOctree.cpp
index 83a0d0cc..f665eb8c 100644
--- a/src/util/PolyOctree.cpp
+++ b/src/util/PolyOctree.cpp
@@ -1,5 +1,7 @@
 #include "PolyOctree.h"
 #include "util.h"
+#include <string.h>
+#include <algorithm>
 
 PolyOctant::PolyOctant(vec3 min, vec3 max) {
     this->min = min;
@@ -96,4 +98,4 @@ void PolygonOctree::getPolysInRegion(PolyOctant* node, Polygon3D* poly, int curr
             getPolysInRegion(node->children[i], poly, currentDepth + 1, regionPolys);
         }
     }
-}
\ No newline at end of file
+}
diff --git a/src/util/Polygon3D.cpp b/src/util/Polygon3D.cpp
index 6af7b17f..94ce5d7b 100644
--- a/src/util/Polygon3D.cpp
+++ b/src/util/Polygon3D.cpp
@@ -2,6 +2,7 @@
 #include "util.h"
 #include "Renderer.h"
 #include "globals.h"
+#include <float.h>
 
 #define COLINEAR_EPSILON 0.125f
 #define SAME_VERT_EPSILON 0.125f
diff --git a/src/util/util.cpp b/src/util/util.cpp
index 6feb895b..9235d3dd 100644
--- a/src/util/util.cpp
+++ b/src/util/util.cpp
@@ -4,6 +4,11 @@
 #include "colors.h"
 #include "mat4x4.h"
 #include "globals.h"
+#include <cstdarg>
+#include <iostream>
+#include <algorithm>
+#include <float.h>
+
 #ifdef WIN32
 #include <Windows.h>
 #include <Shlobj.h>