Index: trunk/src_plugins/import_gcode/gcode_vm.c
===================================================================
--- trunk/src_plugins/import_gcode/gcode_vm.c	(revision 844)
+++ trunk/src_plugins/import_gcode/gcode_vm.c	(revision 845)
@@ -41,6 +41,27 @@
 #define DEG2RAD (G_PI/180.0)
 #define RAD2DEG (180.0/G_PI)
 
+/* Implementation idea borrowed from an old gcc (GPL'd) */
+static double gcode_round(double x)
+{
+	double t;
+
+/* We should check for inf here, but inf is not in C89 */
+
+	if (x >= 0.0) {
+		t = ceil(x);
+		if (t - x > 0.5)
+			t -= 1.0;
+		return t;
+	}
+
+	t = ceil(-x);
+	if ((t + x) > 0.5)
+		t -= 1.0;
+	return -t;
+}
+
+
 #define LIST_APPEND(FIRST, LAST, ITEM) \
 	do { \
 		if (FIRST != NULL) { \
@@ -191,7 +212,7 @@
 			case T_FUP:    a = pop(ctx); push(ctx, ceil(a)); break;
 			case T_EXP:    a = pop(ctx); push(ctx, exp(a)); break;
 			case T_LN:     a = pop(ctx); push(ctx, log(a)); break;
-			case T_ROUND:  a = pop(ctx); push(ctx, round(a)); break;
+			case T_ROUND:  a = pop(ctx); push(ctx, gcode_round(a)); break;
 			case T_SQRT:   a = pop(ctx); push(ctx, sqrt(a)); break;
 			case T_MOD:    a = pop(ctx); b = pop(ctx); push(ctx, fmod(a,b)); break;
 			case T_OR:     a = pop(ctx); b = pop(ctx); push(ctx, (a!=0) || (b!=0)); break;