diff --git a/src/testdir/test_vim9_expr.vim b/src/testdir/test_vim9_expr.vim
index faaa915..2c67103 100644
--- a/src/testdir/test_vim9_expr.vim
+++ b/src/testdir/test_vim9_expr.vim
@@ -2045,6 +2045,13 @@
       assert_equal(6, 0x6)
       assert_equal(15, 0xf)
       assert_equal(255, 0xff)
+
+      const INFTY = 1.0 / 0.0
+      def Test()
+        assert_equal(1, isinf(INFTY))
+        assert_equal(-1, isinf(-INFTY))
+      enddef
+      Test()
   END
   v9.CheckDefAndScriptSuccess(lines)
 enddef
diff --git a/src/version.c b/src/version.c
index 9c9d025..029652e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1107,
+/**/
     1106,
 /**/
     1105,
diff --git a/src/vim9expr.c b/src/vim9expr.c
index 7ec3ee9..b4e201e 100644
--- a/src/vim9expr.c
+++ b/src/vim9expr.c
@@ -1757,22 +1757,14 @@
 	    --p;
 	if (*p == '-' || *p == '+')
 	{
-	    int		negate = *p == '-';
-	    isn_T	*isn;
-	    type_T	*type;
-
-	    type = get_type_on_stack(cctx, 0);
-	    if (type != &t_float && need_type(type, &t_number,
+	    type_T *type = get_type_on_stack(cctx, 0);
+	    if (type->tt_type != VAR_FLOAT && need_type(type, &t_number,
 					    -1, 0, cctx, FALSE, FALSE) == FAIL)
 		return FAIL;
 
 	    // only '-' has an effect, for '+' we only check the type
-	    if (negate)
-	    {
-		isn = generate_instr(cctx, ISN_NEGATENR);
-		if (isn == NULL)
-		    return FAIL;
-	    }
+	    if (*p == '-' && generate_instr(cctx, ISN_NEGATENR) == NULL)
+		return FAIL;
 	}
 	else if (numeric_only)
 	{