diff --git a/engine/common/common.c b/engine/common/common.c
index 666aa2fc..f00297d7 100644
--- a/engine/common/common.c
+++ b/engine/common/common.c
@@ -943,11 +943,11 @@ void GAME_EXPORT pfnResetTutorMessageDecayData( void )
 
 static void Test_LZSS( void )
 {
-	char poison1[8192];
+	char poison1[8192] MAYBE_UNUSED;
 	byte in[256];
-	char poison2[8192];
+	char poison2[8192] MAYBE_UNUSED;
 	byte out[256];
-	char poison3[8192];
+	char poison3[8192] MAYBE_UNUSED;
 
 	lzss_header_t *hdr = (lzss_header_t *)in;
 	uint result;
diff --git a/engine/common/munge.c b/engine/common/munge.c
index 22436ffc..9b167512 100644
--- a/engine/common/munge.c
+++ b/engine/common/munge.c
@@ -92,7 +92,7 @@ void COM_UnMunge2( byte *data, size_t len, int seq )
 }
 
 #if XASH_ENGINE_TESTS // not used in client, keep for tests only
-void COM_Munge3( byte *data, size_t len, int seq )
+static void COM_Munge3( byte *data, size_t len, int seq )
 {
 	COM_GenericMunge( data, len, seq, mungify_table3, false );
 }
diff --git a/engine/common/system.c b/engine/common/system.c
index ec646779..c871aaa2 100644
--- a/engine/common/system.c
+++ b/engine/common/system.c
@@ -594,7 +594,7 @@ qboolean Sys_NewInstance( const char *gamedir, const char *finalmsg )
 	exit( 0 );
 #else
 	int exelen;
-	char *exe, **newargs;
+	char *exe = NULL, **newargs;
 
 	// don't use engine allocation utils here
 	// they will be freed after Host_Shutdown
diff --git a/engine/platform/posix/crash_libbacktrace.c b/engine/platform/posix/crash_libbacktrace.c
index b9130e4d..7380fdaf 100644
--- a/engine/platform/posix/crash_libbacktrace.c
+++ b/engine/platform/posix/crash_libbacktrace.c
@@ -61,10 +61,12 @@ static void Sys_AppendPrint( struct print_data *pd, const char *fmt, ... )
 
 	if( len > 0 )
 	{
+		ssize_t unused;
 		if( pd->logfd >= 0 )
-			write( pd->logfd, pd->message, len );
+			unused = write( pd->logfd, pd->message, len );
 
-		write( STDERR_FILENO, pd->message, len );
+		unused = write( STDERR_FILENO, pd->message, len );
+		(void)unused;
 
 		pd->message += len;
 		pd->len += len;
diff --git a/engine/platform/posix/crash_posix.c b/engine/platform/posix/crash_posix.c
index 9461b452..3965fb3b 100644
--- a/engine/platform/posix/crash_posix.c
+++ b/engine/platform/posix/crash_posix.c
@@ -46,7 +46,7 @@ static void Sys_Crash( int signal, siginfo_t *si, void *context )
 	len += Q_snprintf( crash_message + len, sizeof( crash_message ) - len, "Crash: signal %d errno %d with code %d at %p\n", signal, si->si_errno, si->si_code, si->si_addr );
 #endif
 
-	write( STDERR_FILENO, crash_message, len );
+	ssize_t unused = write( STDERR_FILENO, crash_message, len );
 
 #if XASH_ANDROID
 	__android_log_write( ANDROID_LOG_FATAL, "Xash", crash_message );
@@ -55,7 +55,8 @@ static void Sys_Crash( int signal, siginfo_t *si, void *context )
 	// now get log fd and write trace directly to log
 	int logfd = Sys_LogFileNo();
 	if( logfd >= 0 )
-		write( logfd, crash_message, len );
+		unused = write( logfd, crash_message, len );
+	(void)unused;
 
 #if HAVE_LIBBACKTRACE
 	qboolean detailed_message = false;