From b9e4db6642bad4b65d1810bcfc5364a658ca92b0 Mon Sep 17 00:00:00 2001
From: Tulio Magno Quites Machado Filho <tuliom@redhat.com>
Date: Thu, 16 May 2024 13:43:43 -0300
Subject: [PATCH] Fix rhbz #2248872

Ensure the versioned llvm-config alternative gets removed during major
upgrades of the non-compat package.

Also add code that removes the versioned llvm-config alternatives of
the previous 3 LLVM versions. These versions didn't remove their own
versioned llvm-config alternative, leading to broken output, e.g.
llvm-config-16 points to llvm-config-64 from LLVM 17.
---
 llvm.spec | 26 ++++++++++++++++++++++----
 1 file changed, 22 insertions(+), 4 deletions(-)

diff --git a/llvm.spec b/llvm.spec
index 08e85be..34bcf94 100644
--- a/llvm.spec
+++ b/llvm.spec
@@ -93,6 +93,16 @@ exec &>> >(/usr/bin/ts)
 %{_sbindir}/update-alternatives --install %{_bindir}/llvm-config%{exec_suffix} llvm-config%{exec_suffix} %{install_bindir}/llvm-config%{exec_suffix}-%{__isa_bits} %{__isa_bits}
 %if %{without compat_build}
 %{_sbindir}/update-alternatives --install %{_bindir}/llvm-config-%{maj_ver} llvm-config-%{maj_ver} %{install_bindir}/llvm-config%{exec_suffix}-%{__isa_bits} %{__isa_bits}
+
+# During the upgrade from LLVM 16 (F38) to LLVM 17 (F39), we found out the
+# main llvm-devel package was leaving entries in the alternatives system.
+# Try to remove them now.
+for v in 14 15 16; do
+  if [[ -e %{_bindir}/llvm-config-$v
+        && "x$(%{_bindir}/llvm-config-$v --version | awk -F . '{ print $1 }')" != "x$v" ]]; then
+    %{_sbindir}/update-alternatives --remove llvm-config-$v %{install_bindir}/llvm-config%{exec_suffix}-%{__isa_bits}
+  fi
+done
 %endif
 
 %postun -n %{pkg_name_llvm}-devel
@@ -101,12 +111,20 @@ exec &>> >(/usr/bin/ts)
 %endif
 if [ $1 -eq 0 ]; then
   %{_sbindir}/update-alternatives --remove llvm-config%{exec_suffix} %{install_bindir}/llvm-config%{exec_suffix}-%{__isa_bits}
-%if %{without compat_build}
-  %{_sbindir}/update-alternatives --remove llvm-config-%{maj_ver} %{install_bindir}/llvm-config%{exec_suffix}-%{__isa_bits}
-%endif
 fi
+%if %{without compat_build}
+# When upgrading between minor versions (i.e. from x.y.1 to x.y.2), we must
+# not remove the alternative.
+# However, during a major version upgrade (i.e. from 16.x.y to 17.z.w), the
+# alternative must be removed in order to give priority to a newly installed
+# compat package.
+if [[ $1 -eq 0
+      || "x$(%{_bindir}/llvm-config-%{maj_ver} --version | awk -F . '{ print $1 }')" != "x%{maj_ver}" ]]; then
+  %{_sbindir}/update-alternatives --remove llvm-config-%{maj_ver} %{install_bindir}/llvm-config%{exec_suffix}-%{__isa_bits}
+fi
+%endif
 
 %include %{_sourcedir}/files.spec.inc
 
 %changelog
-%include %{_sourcedir}/changelog.spec.inc
\ No newline at end of file
+%include %{_sourcedir}/changelog.spec.inc