Auto merge of #67220 - Centril:rollup-n3u9wd5, r=Centril

Rollup of 6 pull requests

Successful merges:

 - #66881 (Optimize Ord trait implementation for bool)
 - #67015 (Fix constant propagation for scalar pairs)
 - #67074 (Add options to --extern flag.)
 - #67164 (Ensure that panicking in constants eventually errors)
 - #67174 (Remove `checked_add` in `Layout::repeat`)
 - #67205 (Make `publish_toolstate.sh` executable)

Failed merges:

r? @ghost

1 files changed, 5 insertions, 2 deletions

diff --git a/src/libcore/alloc.rs b/src/libcore/alloc.rs
index 4cfd6527deb..5c24e3d8f5d 100644
--- a/src/libcore/alloc.rs
+++ b/src/libcore/alloc.rs
@@ -239,8 +239,11 @@ impl Layout {
     #[unstable(feature = "alloc_layout_extra", issue = "55724")]
     #[inline]
     pub fn repeat(&self, n: usize) -> Result<(Self, usize), LayoutErr> {
-        let padded_size = self.size().checked_add(self.padding_needed_for(self.align()))
-            .ok_or(LayoutErr { private: () })?;
+        // This cannot overflow. Quoting from the invariant of Layout:
+        // > `size`, when rounded up to the nearest multiple of `align`,
+        // > must not overflow (i.e., the rounded value must be less than
+        // > `usize::MAX`)
+        let padded_size = self.size() + self.padding_needed_for(self.align());
         let alloc_size = padded_size.checked_mul(n)
             .ok_or(LayoutErr { private: () })?;