As pointed out by claudio, existing llvm-19 installs won't update
since it was unlinked from the tree, so add some conflict and pkgpath
dances similar to the ones that were done for 19. Since 21 needs to
stay for a good while, this is a bit different.

Tested with various combinations and versions of llvm subpackages
installed on stable updated to current across python 3.13 -> 3.14
and llvm 22.

Index: devel/llvm/22/Makefile
===================================================================
RCS file: /cvs/ports/devel/llvm/22/Makefile,v
diff -u -p -r1.17 Makefile
--- devel/llvm/22/Makefile	18 Jun 2026 07:03:09 -0000	1.17
+++ devel/llvm/22/Makefile	1 Jul 2026 09:56:24 -0000
@@ -2,6 +2,11 @@ LLVM_MAJOR =	22
 LLVM_VERSION =	${LLVM_MAJOR}.1.8
 LLVM_PKGSPEC =	>=22,<23
 
+REVISION-main =		0
+REVISION-libcxx =	0
+REVISION-lldb =		0
+REVISION-python =	0
+
 SHARED_LIBS +=	LLVM		0.0 \
 		LTO		0.0 \
 		Remarks		0.0 \
Index: devel/llvm/22/pkg/PLIST-libcxx
===================================================================
RCS file: /cvs/ports/devel/llvm/22/pkg/PLIST-libcxx,v
diff -u -p -r1.2 PLIST-libcxx
--- devel/llvm/22/pkg/PLIST-libcxx	17 Jun 2026 20:55:12 -0000	1.2
+++ devel/llvm/22/pkg/PLIST-libcxx	1 Jul 2026 09:56:24 -0000
@@ -1,6 +1,12 @@
 @option no-default-conflict
 @option is-branch
 @conflict libcxx-${LLVM_PKGSPEC}
+@conflict libcxx-<21
+@pkgpath devel/llvm/13,-libcxx
+@pkgpath devel/llvm/16,-libcxx
+@pkgpath devel/llvm/18,-libcxx
+@pkgpath devel/llvm/19,-libcxx
+@pkgpath devel/llvm/20,-libcxx
 ${LLVM_BASE}/include/c++/
 ${LLVM_BASE}/include/c++/v1/
 ${LLVM_BASE}/include/c++/v1/__algorithm/
Index: devel/llvm/22/pkg/PLIST-lldb
===================================================================
RCS file: /cvs/ports/devel/llvm/22/pkg/PLIST-lldb,v
diff -u -p -r1.2 PLIST-lldb
--- devel/llvm/22/pkg/PLIST-lldb	9 Jun 2026 11:24:09 -0000	1.2
+++ devel/llvm/22/pkg/PLIST-lldb	1 Jul 2026 09:56:24 -0000
@@ -1,7 +1,13 @@
 @option no-default-conflict
 @option is-branch
 @conflict lldb-${LLVM_PKGSPEC}
+@conflict lldb-<21
 @conflict llvm->=22.1.0,<22.1.7p0
+@pkgpath devel/llvm/13,-lldb
+@pkgpath devel/llvm/16,-lldb
+@pkgpath devel/llvm/18,-lldb
+@pkgpath devel/llvm/19,-lldb
+@pkgpath devel/llvm/20,-lldb
 bin/lldb-${LLVM_MAJOR}
 bin/lldb-argdumper-${LLVM_MAJOR}
 bin/lldb-dap-${LLVM_MAJOR}
Index: devel/llvm/22/pkg/PLIST-main
===================================================================
RCS file: /cvs/ports/devel/llvm/22/pkg/PLIST-main,v
diff -u -p -r1.2 PLIST-main
--- devel/llvm/22/pkg/PLIST-main	9 Jun 2026 11:24:09 -0000	1.2
+++ devel/llvm/22/pkg/PLIST-main	1 Jul 2026 09:56:24 -0000
@@ -1,7 +1,14 @@
 @option no-default-conflict
 @option is-branch
 @conflict llvm-${LLVM_PKGSPEC}
+@conflict llvm-<21
 @conflict lldb->=22.1.0,<22.1.7p0
+@pkgpath devel/llvm/13,-main
+@pkgpath devel/llvm/16,-main
+@pkgpath devel/llvm/17,-main
+@pkgpath devel/llvm/18,-main
+@pkgpath devel/llvm/19,-main
+@pkgpath devel/llvm/20,-main
 bin/amdgpu-arch-${LLVM_MAJOR}
 bin/analyze-build-${LLVM_MAJOR}
 bin/bugpoint-${LLVM_MAJOR}
Index: devel/llvm/22/pkg/PLIST-python
===================================================================
RCS file: /cvs/ports/devel/llvm/22/pkg/PLIST-python,v
diff -u -p -r1.1.1.1 PLIST-python
--- devel/llvm/22/pkg/PLIST-python	25 Feb 2026 13:31:45 -0000	1.1.1.1
+++ devel/llvm/22/pkg/PLIST-python	1 Jul 2026 09:56:24 -0000
@@ -1,6 +1,13 @@
 @option no-default-conflict
 @option is-branch
 @conflict ${MODPY_PY_PREFIX}llvm-${LLVM_PKGSPEC}
+@conflict ${MODPY_PY_PREFIX}llvm-<21
+@pkgpath devel/llvm/13,-python
+@pkgpath devel/llvm/16,-python
+@pkgpath devel/llvm/17,-python
+@pkgpath devel/llvm/18,-python
+@pkgpath devel/llvm/19,-python
+@pkgpath devel/llvm/20,-python
 ${LLVM_BASE}/lib/python${MODPY_VERSION}/site-packages/clang/
 ${LLVM_BASE}/lib/python${MODPY_VERSION}/site-packages/clang/__init__.py
 ${LLVM_BASE}/lib/python${MODPY_VERSION}/site-packages/clang/${MODPY_PYCACHE}/