Temporarily skip PGO on RHEL ppc64le

Resolves: RHEL-81601
Resolves: RHEL-81615

rust.spec

@@ -1,6 +1,6 @@
 Name:           rust
 Version:        1.86.0
-Release:        1%{?dist}
+Release:        2%{?dist}
 Summary:        The Rust Programming Language
 License:        (Apache-2.0 OR MIT) AND (Artistic-2.0 AND BSD-3-Clause AND ISC AND MIT AND MPL-2.0 AND Unicode-3.0)
 # ^ written as: (rust itself) and (bundled libraries)
@@ -867,6 +867,9 @@ test -r "%{profiler}"
 # Skipping PGO on s390x until we get LLVM 20, due to
 # https://github.com/llvm/llvm-project/issues/124001
 %ifnarch s390x
+# rustc is exibiting signs of miscompilation on pwr9+pgo (root cause TBD),
+# so we're skipping pgo on rhel ppc64le for now.
+%if !( 0%{?rhel} && "%{_target_cpu}" == "ppc64le" )
 %if %with rustc_pgo
 # Build the compiler with profile instrumentation
 %define profraw $PWD/build/profiles
@@ -883,6 +886,7 @@ rm -r "%{profraw}" build/%{rust_triple}/stage2*/
 %global __x %{__x} --rust-profile-use="%{profdata}"
 %endif
 %endif
+%endif
 
 # Build the compiler normally (with or without PGO)
 %{__x} build sysroot
@@ -1197,6 +1201,9 @@ rm -rf "./build/%{rust_triple}/stage2-tools/%{rust_triple}/cit/"
 
 
 %changelog
+* Thu Apr 24 2025 Josh Stone <jistone@redhat.com> - 1.86.0-2
+- Temporarily skip PGO on RHEL ppc64le
+
 * Tue Apr 08 2025 Josh Stone <jistone@redhat.com> - 1.86.0-1
 - Update to 1.86.0