1 files changed, 6 insertions, 2 deletions
diff --git a/library/core/src/fmt/mod.rs b/library/core/src/fmt/mod.rs
index 84cf1753f86..0e2e869a920 100644
--- a/library/core/src/fmt/mod.rs
+++ b/library/core/src/fmt/mod.rs
@@ -352,7 +352,11 @@ impl<'a> ArgumentV1<'a> {
     }
 
     fn as_usize(&self) -> Option<usize> {
-        if self.formatter as usize == USIZE_MARKER as usize {
+        // We are type punning a bit here: USIZE_MARKER only takes an &usize but
+        // formatter takes an &Opaque. Rust understandably doesn't think we should compare
+        // the function pointers if they don't have the same signature, so we cast to
+        // pointers to convince it that we know what we're doing.
+        if self.formatter as *mut u8 == USIZE_MARKER as *mut u8 {
             // SAFETY: The `formatter` field is only set to USIZE_MARKER if
             // the value is a usize, so this is safe
             Some(unsafe { *(self.value as *const _ as *const usize) })
@@ -2246,7 +2250,7 @@ impl<T: ?Sized> Pointer for *const T {
             }
             f.flags |= 1 << (FlagV1::Alternate as u32);
 
-            let ret = LowerHex::fmt(&(ptr as usize), f);
+            let ret = LowerHex::fmt(&(ptr.addr()), f);
 
             f.width = old_width;
             f.flags = old_flags;