diff --git a/miscutils/bc.c b/miscutils/bc.c
index a5fcaf3bc..eaa28a94a 100644
--- a/miscutils/bc.c
+++ b/miscutils/bc.c
@@ -2655,9 +2655,13 @@ static FAST_FUNC void bc_result_free(void *result)
 
 static void bc_lex_lineComment(BcLex *l)
 {
+	// Try: echo -n '#foo' | bc
+	size_t i;
 	l->t.t = BC_LEX_WHITESPACE;
-	while (l->i < l->len && l->buf[l->i++] != '\n');
-	--l->i;
+	i = l->i;
+	while (i < l->len && l->buf[i] != '\n')
+		i++;
+	l->i = i;
 }
 
 static void bc_lex_whitespace(BcLex *l)
@@ -2889,8 +2893,8 @@ static BC_STATUS zbc_lex_next(BcLex *l)
 	// Comments are also BC_LEX_WHITESPACE tokens and eaten here.
 	s = BC_STATUS_SUCCESS;
 	do {
-		l->t.t = BC_LEX_EOF;
 		if (l->i == l->len) {
+			l->t.t = BC_LEX_EOF;
 			if (!G.input_fp)
 				RETURN_STATUS(BC_STATUS_SUCCESS);
 			if (!bc_lex_more_input(l)) {
diff --git a/testsuite/bc.tests b/testsuite/bc.tests
index e0a45a8bd..e303cf6ae 100755
--- a/testsuite/bc.tests
+++ b/testsuite/bc.tests
@@ -16,6 +16,11 @@ testing "bc comment 2: /*/ is not a closed comment" \
 	"4\n" \
 	"" "1 /*/ + 2 */ + 3"
 
+testing "bc comment 3: unterminated #comment" \
+	"bc" \
+	"" \
+	"" "#foo"  # no trailing newline
+
 testing "bc backslash 1" \
 	"bc" \
 	"3\n" \