Merge pull request #364 from dbrotz/fix-362

Don't append invalid characters to symbol name

test/asm/label-macro-arg.asm

@@ -0,0 +1,27 @@
+m1: MACRO
+x\1
+ENDM
+
+S EQUS "y"
+S2 EQUS "yy"
+
+m2: MACRO
+S\1
+ENDM
+
+	m1 = 5
+	m2 = 6
+	m1 x = 7
+	m2 2 = 8
+
+	printv x
+	printt "\n"
+
+	printv y
+	printt "\n"
+
+	printv xx
+	printt "\n"
+
+	printv yy
+	printt "\n"

test/asm/label-macro-arg.out

@@ -0,0 +1,4 @@
+$5
+$6
+$7
+$8

test/asm/label-macro-arg.out.pipe

@@ -0,0 +1,4 @@
+$5
+$6
+$7
+$8