1 files changed, 7 insertions, 4 deletions
diff --git a/src/cmd/gc/lex.c b/src/cmd/gc/lex.c
index 05671cc38..586dc47d5 100644
--- a/src/cmd/gc/lex.c
+++ b/src/cmd/gc/lex.c
@@ -811,10 +811,13 @@ talph:
 				cp[c1++] = c;
 				if(fullrune(cp, c1)) {
 					chartorune(&rune, cp);
-					 if(isfrog(rune)) {
-					 	yyerror("illegal character 0x%ux", rune);
-					 	goto l0;
-					 }
+					if(isfrog(rune)) {
+						yyerror("illegal character 0x%ux", rune);
+						goto l0;
+					}
+					// 0xb7 · is used for internal names
+					if(!isalpharune(c) && !isdigitrune(c) && c != 0xb7)
+						yyerror("invalid identifier character 0x%ux", rune);
 					break;
 				}
 				c = getc();