Never consider int and float vars for `FnPtr` candidates

This solves a regression where `0.0.cmp()` was ambiguous when a custom
trait with a `cmp` method was in scope.

FOr integers it shouldn't be a problem in practice so I wasn't able to
add a test.

1 files changed, 10 insertions, 0 deletions

diff --git a/tests/ui/fn/fn-ptr-trait-int-float-infer-var.rs b/tests/ui/fn/fn-ptr-trait-int-float-infer-var.rs
new file mode 100644
index 00000000000..eec7da044c0
--- /dev/null
+++ b/tests/ui/fn/fn-ptr-trait-int-float-infer-var.rs
@@ -0,0 +1,10 @@
+// check-pass
+trait MyCmp {
+    fn cmp(&self) {}
+}
+impl MyCmp for f32 {}
+
+fn main() {
+    // Ensure that `impl<F: FnPtr> Ord for F` is never considered for int and float infer vars.
+    0.0.cmp();
+}