diff --git a/desmume/src/commandline.cpp b/desmume/src/commandline.cpp
index 426dd7817..ee3a2c75b 100644
--- a/desmume/src/commandline.cpp
+++ b/desmume/src/commandline.cpp
@@ -251,7 +251,7 @@ bool CommandLine::validate()
 	if (_cpu_mode < -1 || _cpu_mode > 1) {
 		g_printerr("Invalid cpu mode emulation (0 - interpreter, 1 - dynarec)\n");
 	}
-	if (_cpu_mode != -1 && (_jit_size < 1 || _jit_size > 100)) {
+	if (_jit_size < -1 && (_jit_size == 0 || _jit_size > 100)) {
 		g_printerr("Invalid jit block size [1..100]. set to 100\n");
 	}
 #endif