test opt-level 2

ci.sh

@@ -25,8 +25,8 @@ function run_tests {
   ./miri test --locked
   if ! [ -n "${MIRI_TEST_TARGET+exists}" ]; then
     # Only for host architecture: tests with MIR optimizations
-    # FIXME: only testing level 1 because of <https://github.com/rust-lang/rust/issues/73223>.
-    MIRI_TEST_FLAGS="-Z mir-opt-level=1" ./miri test --locked
+    # FIXME: only testing level 2 because of <https://github.com/rust-lang/rust/issues/76432>.
+    MIRI_TEST_FLAGS="-Z mir-opt-level=2" ./miri test --locked
   fi
   # "miri test" has built the sysroot for us, now this should pass without
   # any interactive questions.

tests/run-pass/float.rs

@@ -1,3 +1,5 @@
+// compile-flags: -Zmir-opt-level=0
+// FIXME: Using opt-level 2 here makes the test take forever (https://github.com/rust-lang/rust/issues/76433).
 #![feature(stmt_expr_attributes)]
 use std::fmt::Debug;