diff --git a/.github/workflows/makefile.yml b/.github/workflows/makefile.yml
index f604641..c2a9046 100644
--- a/.github/workflows/makefile.yml
+++ b/.github/workflows/makefile.yml
@@ -26,16 +26,27 @@ jobs:
 
     steps:
     - name: Install dependencies
-      run: sudo apt install -y astyle
+      run: sudo apt install -y astyle cppcheck catch2
 
     - uses: actions/checkout@v4
       with:
         submodules: recursive
 
-    - name: check_format
+    - name: format_check
       working-directory: ./
       run: ./format.sh --dry
 
+    - name: cpp_check
+      working-directory: ./
+      run: ./cpp_check.sh
+
+    - name: unit_tests
+      working-directory: build/tests
+      run: | 
+        cmake -S . -B build
+        cmake --build build
+        ./build/osp2_tests
+
     - name: build-qvm
       working-directory: build/qvm
       run: | 
@@ -62,6 +73,7 @@ jobs:
 
   mingw:
     name: MinGW GCC
+    needs: linux 
 
     runs-on: windows-2022
 
diff --git a/code/cgame/cg_consolecmds.c b/code/cgame/cg_consolecmds.c
index 52f75d7..6e4b480 100644
--- a/code/cgame/cg_consolecmds.c
+++ b/code/cgame/cg_consolecmds.c
@@ -354,11 +354,14 @@ void CG_OSPServerVersion_f(void)
 		Q_strncpyz(buf, ptr, 1024);
 		pos = buf;
 
-		while (pos != 0)
+		while (*pos != 0)
 		{
 			pack = pos;
 			pos = strchr(pos, ' ');
-			if (pos == NULL) return;
+			if (pos == NULL)
+			{
+				break;
+			}
 			*pos = 0;
 			CG_Printf("   ^7%s\n", pack);
 
diff --git a/code/cgame/cg_local.h b/code/cgame/cg_local.h
index a58f020..83ac840 100644
--- a/code/cgame/cg_local.h
+++ b/code/cgame/cg_local.h
@@ -1545,6 +1545,10 @@ const char* CG_ConfigString(int index);
 const char* CG_Argv(int arg);
 
 void QDECL CG_Printf(const char* msg, ...);
+
+#ifdef __GNUC__
+__attribute__((noreturn))
+#endif
 void QDECL CG_Error(const char* msg, ...);
 void CG_PrintLog(char* msg);
 
diff --git a/code/cgame/cg_main.c b/code/cgame/cg_main.c
index 94d734e..4336efd 100644
--- a/code/cgame/cg_main.c
+++ b/code/cgame/cg_main.c
@@ -714,6 +714,10 @@ cvarTable_t* CG_GetCgCvarByName(const char* name)
 	{
 		target = target->next;
 	}
+	if (target == NULL)
+	{
+		return NULL;
+	}
 	return Q_stricmp(name, target->cvarName) == 0 ? target : NULL;
 }
 
@@ -870,6 +874,9 @@ void QDECL CG_Printf(const char* msg, ...)
 	trap_Print(text);
 }
 
+#ifdef __GNUC__
+__attribute__((noreturn))
+#endif
 void QDECL CG_Error(const char* msg, ...)
 {
 	va_list     argptr;
@@ -881,11 +888,17 @@ void QDECL CG_Error(const char* msg, ...)
 
 	CG_PrintLog(text);
 	trap_Error(text);
+#ifdef __GNUC__
+	while (1) {}
+#endif
 }
 
 #ifndef CGAME_HARD_LINKED
 // this is only here so the functions in q_shared.c and bg_*.c can link (FIXME)
 
+#ifdef __GNUC__
+__attribute__((noreturn))
+#endif
 void QDECL Com_Error(int level, const char* error, ...)
 {
 	va_list     argptr;
diff --git a/code/cgame/cg_osphud.c b/code/cgame/cg_osphud.c
index 221fcaa..9f85acd 100644
--- a/code/cgame/cg_osphud.c
+++ b/code/cgame/cg_osphud.c
@@ -2717,7 +2717,8 @@ static float CG_OSPHUDDrawScores(float y)
 		y -= fontScoresH + 8;
 		y1 = y;
 
-		fontStatusbarH = fontStatusbarW;
+		CG_OSPGetClientFontSize(&cf_Statusbar, &fontStatusbarW, &fontStatusbarH);
+
 		score = cg.snap->ps.persistant[PERS_SCORE];
 		spectator = (cg.snap->ps.persistant[PERS_TEAM] == TEAM_SPECTATOR);
 
diff --git a/code/cgame/cg_osputil.c b/code/cgame/cg_osputil.c
index 2a99ca7..f118306 100644
--- a/code/cgame/cg_osputil.c
+++ b/code/cgame/cg_osputil.c
@@ -62,9 +62,9 @@ void CG_OSPNormalizeText(char* src, int size, char* dst)
 int CG_OSPGetNormalizedStringSize(const char* str)
 {
 	int i = 0;
-	while (*str)
+	while (str && *str)
 	{
-		if (str && *str == '^' && *(str + 1) != 0 &&  *(str + 1) != '^')
+		if (*str == '^' && *(str + 1) != 0 &&  *(str + 1) != '^')
 		{
 			if (*(str + 1) == 'x' || *(str + 1) == 'X')
 			{
diff --git a/code/cgame/cg_snapshot.c b/code/cgame/cg_snapshot.c
index 0acaa80..6bdad62 100644
--- a/code/cgame/cg_snapshot.c
+++ b/code/cgame/cg_snapshot.c
@@ -166,7 +166,7 @@ static void CG_TransitionSnapshot(void)
 	CG_ExecuteNewServerCommands(cg.nextSnap->serverCommandSequence);
 
 	// clear the currentValid flag for all entities in the existing snapshot
-	for (i = 0 ; i < cg.snap->numEntities ; i++)
+	for (i = 0 ; i < cg.snap->numEntities ; ++i)
 	{
 		cent = &cg_entities[ cg.snap->entities[ i ].number ];
 		cent->currentValid = qfalse;
@@ -191,7 +191,6 @@ static void CG_TransitionSnapshot(void)
 	cg.nextSnap = NULL;
 
 	// check for playerstate transition events
-	if (oldFrame)
 	{
 		playerState_t*   ops, *ps;
 
@@ -256,7 +255,7 @@ static void CG_SetNextSnap(snapshot_t* snap)
 
 	// if the next frame is a teleport for the playerstate, we
 	// can't interpolate during demos
-	if (cg.snap && ((snap->ps.eFlags ^ cg.snap->ps.eFlags) & EF_TELEPORT_BIT))
+	if ((snap->ps.eFlags ^ cg.snap->ps.eFlags) & EF_TELEPORT_BIT)
 	{
 		cg.nextFrameTeleport = qtrue;
 	}
diff --git a/code/cgame/cg_superhud.c b/code/cgame/cg_superhud.c
index 6f3cf5d..525e9ed 100644
--- a/code/cgame/cg_superhud.c
+++ b/code/cgame/cg_superhud.c
@@ -423,6 +423,11 @@ void CG_SHUDEventTeamChat(const char* message)
 	int index;
 	superhudGlobalContext_t* ctx = CG_SHUDGetContext();
 
+	if (message == NULL)
+	{
+		return;
+	}
+
 	if (customLocationsEnabled != 0)
 	{
 		char* cloc_begin, *cloc_end;
diff --git a/code/qcommon/q_math.c b/code/qcommon/q_math.c
index 905361e..f673054 100644
--- a/code/qcommon/q_math.c
+++ b/code/qcommon/q_math.c
@@ -290,7 +290,7 @@ void ByteToDir(int b, vec3_t dir)
 
 unsigned ColorBytes3(float r, float g, float b)
 {
-	unsigned    i;
+	unsigned    i = 0;
 
 	((byte*)&i)[0] = r * 255;
 	((byte*)&i)[1] = g * 255;
@@ -301,7 +301,7 @@ unsigned ColorBytes3(float r, float g, float b)
 
 unsigned ColorBytes4(float r, float g, float b, float a)
 {
-	unsigned    i;
+	unsigned    i = 0;
 
 	((byte*)&i)[0] = r * 255;
 	((byte*)&i)[1] = g * 255;
@@ -631,6 +631,7 @@ float Q_fabs(float f)
 	tmp &= 0x7FFFFFFF;
 	return * (float*) &tmp;
 }
+
 #endif
 
 //============================================================
diff --git a/code/qcommon/q_shared.c b/code/qcommon/q_shared.c
index ece27dc..2a9029c 100644
--- a/code/qcommon/q_shared.c
+++ b/code/qcommon/q_shared.c
@@ -1241,8 +1241,6 @@ void Info_RemoveKey(char* s, const char* key)
 		o = value;
 		while (*s != '\\' && *s)
 		{
-			if (!*s)
-				return;
 			*o++ = *s++;
 		}
 		*o = 0;
@@ -1299,8 +1297,6 @@ void Info_RemoveKey_Big(char* s, const char* key)
 		o = value;
 		while (*s != '\\' && *s)
 		{
-			if (!*s)
-				return;
 			*o++ = *s++;
 		}
 		*o = 0;
diff --git a/code/qcommon/q_shared.h b/code/qcommon/q_shared.h
index 23ecaa4..e3bc9e6 100644
--- a/code/qcommon/q_shared.h
+++ b/code/qcommon/q_shared.h
@@ -593,7 +593,7 @@ extern  vec4_t      colorMdGrey;
 extern  vec4_t      colorDkGrey;
 
 #define Q_COLOR_ESCAPE  '^'
-#define Q_IsColorString(p)  ( p && *(p) == Q_COLOR_ESCAPE && *((p)+1) && *((p)+1) != Q_COLOR_ESCAPE )
+#define Q_IsColorString(p)  (*(p) == Q_COLOR_ESCAPE && *((p)+1) && *((p)+1) != Q_COLOR_ESCAPE )
 
 #define COLOR_BLACK     '0'
 #define COLOR_RED       '1'
@@ -996,6 +996,9 @@ qboolean Info_Validate(const char* s);
 void Info_NextPair(const char** s, char* key, char* value);
 
 // this is only here so the functions in q_shared.c and bg_*.c can link
+#ifdef __GNUC__
+    __attribute__ ((noreturn))
+#endif
 void    QDECL Com_Error(int level, const char* error, ...);
 void    QDECL Com_Printf(const char* msg, ...);
 
diff --git a/cpp_check.sh b/cpp_check.sh
new file mode 100755
index 0000000..4c78620
--- /dev/null
+++ b/cpp_check.sh
@@ -0,0 +1,3 @@
+#!/bin/bash
+RET="$(cppcheck -D__GNUC__ -q -j32 --enable=warning,performance,portability --std=c89 --suppressions-list=./cppcheck_suppress.txt --error-exitcode=1 ./code)"
+exit $RET
diff --git a/cppcheck_suppress.txt b/cppcheck_suppress.txt
new file mode 100644
index 0000000..3341095
--- /dev/null
+++ b/cppcheck_suppress.txt
@@ -0,0 +1,3 @@
+invalidPointerCast
+invalidTestForOverflow
+floatConversionOverflow