[clang-tools-extra] [llvm] [cmake] Properly link against LLVM components (PR #224624)

[Fabrice de Gans via llvm-commits]

https://github.com/Steelskin updated https://github.com/llvm/llvm-project/pull/224624

>From 8b19c980371db379cf16762c62b6161c1438f110 Mon Sep 17 00:00:00 2001
From: Fabrice de Gans <steelskin at gmail.com>
Date: Fri, 18 Sep 2026 14:40:22 +0200
Subject: [PATCH] [cmake] Properly link against LLVM components

The proper way to reference LLVM components is to pass them via the
LLVM_LINK_COMPONENTS variable. This is needed when building LLVM as a
dylib, so the proper dependency (the LLVM library) is passed.

This does not apply to plain add_executable() targets, which should
manually select to link against LLVM or individual LLVM components.

The effort to build LLVM as a dylib is tracked in #109483.
---
 clang-tools-extra/clangd/benchmarks/CMakeLists.txt        | 5 ++++-
 .../clangd/benchmarks/CompletionModel/CMakeLists.txt      | 5 ++++-
 cross-project-tests/CMakeLists.txt                        | 5 ++++-
 .../llvm-prettyprinters/lldb/CMakeLists.txt               | 8 +++++++-
 4 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/clang-tools-extra/clangd/benchmarks/CMakeLists.txt b/clang-tools-extra/clangd/benchmarks/CMakeLists.txt
index 13ca21ad70d81..13beec4919ebf 100644
--- a/clang-tools-extra/clangd/benchmarks/CMakeLists.txt
+++ b/clang-tools-extra/clangd/benchmarks/CMakeLists.txt
@@ -2,10 +2,13 @@ if(CLANGD_DECISION_FOREST)
   add_subdirectory(CompletionModel)
 endif()
 
+set(LLVM_LINK_COMPONENTS
+  Support
+  )
+
 add_benchmark(IndexBenchmark IndexBenchmark.cpp)
 
 target_link_libraries(IndexBenchmark
   PRIVATE
   clangDaemon
-  LLVMSupport
   )
diff --git a/clang-tools-extra/clangd/benchmarks/CompletionModel/CMakeLists.txt b/clang-tools-extra/clangd/benchmarks/CompletionModel/CMakeLists.txt
index 4c7cd779eb3e7..81cf3cc0fca60 100644
--- a/clang-tools-extra/clangd/benchmarks/CompletionModel/CMakeLists.txt
+++ b/clang-tools-extra/clangd/benchmarks/CompletionModel/CMakeLists.txt
@@ -1,7 +1,10 @@
+set(LLVM_LINK_COMPONENTS
+  Support
+  )
+
 add_benchmark(DecisionForestBenchmark DecisionForestBenchmark.cpp)
 
 target_link_libraries(DecisionForestBenchmark
   PRIVATE
   clangDaemon
-  LLVMSupport
   )
diff --git a/cross-project-tests/CMakeLists.txt b/cross-project-tests/CMakeLists.txt
index 85102065e79e6..8961958f6f16e 100644
--- a/cross-project-tests/CMakeLists.txt
+++ b/cross-project-tests/CMakeLists.txt
@@ -7,10 +7,13 @@ set(LLVM_SUBPROJECT_TITLE "Cross-Project")
 
 find_package(Python3 COMPONENTS Interpreter)
 
+set(LLVM_LINK_COMPONENTS
+  Support
+  )
+
 add_llvm_executable(check-gdb-llvm-support
         debuginfo-tests/llvm-prettyprinters/gdb/llvm-support.cpp
 )
-target_link_libraries(check-gdb-llvm-support PRIVATE LLVMSupport)
 
 add_subdirectory(debuginfo-tests/llvm-prettyprinters/lldb)
 
diff --git a/cross-project-tests/debuginfo-tests/llvm-prettyprinters/lldb/CMakeLists.txt b/cross-project-tests/debuginfo-tests/llvm-prettyprinters/lldb/CMakeLists.txt
index e2a9a080fd4c7..ac3efaf641c24 100644
--- a/cross-project-tests/debuginfo-tests/llvm-prettyprinters/lldb/CMakeLists.txt
+++ b/cross-project-tests/debuginfo-tests/llvm-prettyprinters/lldb/CMakeLists.txt
@@ -1,6 +1,12 @@
 add_library(lldb-formatter-test-settings INTERFACE)
 
-target_link_libraries(lldb-formatter-test-settings INTERFACE LLVMSupport)
+# Link the correct LLVM dependency, depending on the configuration.
+if(LLVM_LINK_LLVM_DYLIB)
+  target_link_libraries(lldb-formatter-test-settings INTERFACE LLVM)
+else()
+  target_link_libraries(lldb-formatter-test-settings INTERFACE LLVMSupport)
+endif()
+
 # Unset _FORTIFY_SOURCE since it's incompatible with -O0.
 target_compile_options(lldb-formatter-test-settings INTERFACE -g -O0 -U_FORTIFY_SOURCE)