[2.0.0] Fix CI builds (#5219)

* Fix instruction size test for Rust 1.65.0 (#5188)

Looks like Rust generously shrank our `enum` in 1.65.0, so update the
test assertion to pass CI.

* Use an alternate doxygen download link (#5150)

* Use an alternate doxygen download link

Looks like doxygen.nl is down otherwise.

* Update link

.github/workflows/main.yml

@@ -81,7 +81,7 @@ jobs:
 
     # Build C API documentation
     - run: sudo apt-get update -y && sudo apt-get install -y libclang1-9 libclang-cpp9
-    - run: curl -L https://www.doxygen.nl/files/doxygen-1.9.3.linux.bin.tar.gz | tar xzf -
+    - run: curl -L https://sourceforge.net/projects/doxygen/files/rel-1.9.3/doxygen-1.9.3.linux.bin.tar.gz/download | tar xzf -
     - run: echo "`pwd`/doxygen-1.9.3/bin" >> $GITHUB_PATH
     - run: cd crates/c-api && doxygen doxygen.conf
 

cranelift/codegen/src/isa/x64/inst/mod.rs

@@ -48,7 +48,7 @@ pub struct CallInfo {
 fn inst_size_test() {
     // This test will help with unintentionally growing the size
     // of the Inst enum.
-    assert_eq!(48, std::mem::size_of::<Inst>());
+    assert_eq!(40, std::mem::size_of::<Inst>());
 }
 
 pub(crate) fn low32_will_sign_extend_to_64(x: u64) -> bool {