From 2cf49cc50de2834efdefdfff91f562dc88da3b54 Mon Sep 17 00:00:00 2001
From: Dennis Klein <d.klein@gsi.de>
Date: Tue, 9 Jun 2026 17:04:57 +0200
Subject: [PATCH] ci: fix thread-sanitizer build with lld and PIC googletest

- tsan build failed at link with GNU ld:
  "failed to set dynamic section sizes: bad value" (known binutils +
  ThreadSanitizer incompatibility); install lld and select it via
  -fuse-ld=lld for the tsan job only
- pass -fuse-ld=lld through cxx-flags so it reaches the link line,
  avoiding the semicolon-list pitfall of
  list(APPEND CMAKE_EXE_LINKER_FLAGS ...)
- build the bundled googletest with CMAKE_POSITION_INDEPENDENT_CODE=ON:
  lld rejects R_X86_64_32 relocations from the non-PIC libgtest.a when
  producing the position-independent tsan executable; the bundle is built
  by a separate cmake invocation, so the flag must be set there
---
 .github/workflows/ci.yml              | 5 +++++
 cmake/FairMQBundlePackageHelper.cmake | 1 +
 2 files changed, 6 insertions(+)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 43fb8beb..9b6430e7 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -81,6 +81,7 @@ jobs:
           - name: tsan
             options: ENABLE_SANITIZER_THREAD=ON
             cxx-compiler: clang++
+            cxx-flags: -fuse-ld=lld
 
     steps:
       - uses: actions/checkout@v6
@@ -100,6 +101,10 @@ jobs:
           key: ${{ github.job }}-${{ matrix.sanitizer.name }}
           max-size: 500M
 
+      - name: Install lld
+        if: matrix.sanitizer.name == 'tsan'
+        run: sudo apt-get update && sudo apt-get install -y lld
+
       - name: Configure and Build
         uses: threeal/cmake-action@v2
         with:
diff --git a/cmake/FairMQBundlePackageHelper.cmake b/cmake/FairMQBundlePackageHelper.cmake
index e8bb9586..52ba33b7 100644
--- a/cmake/FairMQBundlePackageHelper.cmake
+++ b/cmake/FairMQBundlePackageHelper.cmake
@@ -68,6 +68,7 @@ function(build_bundled package bundle)
 
     exec(${CMAKE_COMMAND} -S ${${package}_SOURCE_DIR} -B ${${package}_BINARY_DIR} -G ${CMAKE_GENERATOR}
       -DCMAKE_INSTALL_PREFIX=${${package}_INSTALL_DIR} -DBUILD_GMOCK=OFF
+      -DCMAKE_POSITION_INDEPENDENT_CODE=ON
     )
     exec(${CMAKE_COMMAND} --build ${${package}_BINARY_DIR})
     exec(${CMAKE_COMMAND} --build ${${package}_BINARY_DIR} --target install)