ci: Drop BASE_SCRATCH_DIR from LIBCXX_DIR

Using a hard-coded path avoids non-determinism issues and improves CI
UX.

Author: MarcoFalke

ci/test/00_setup_env_native_fuzz_with_msan.sh

@@ -7,7 +7,7 @@
 export LC_ALL=C.UTF-8
 
 export CI_IMAGE_NAME_TAG="ubuntu:22.04"
-LIBCXX_DIR="${BASE_SCRATCH_DIR}/msan/cxx_build/"
+LIBCXX_DIR="/msan/cxx_build/"
 export MSAN_FLAGS="-fsanitize=memory -fsanitize-memory-track-origins=2 -fno-omit-frame-pointer -g -O1 -fno-optimize-sibling-calls"
 LIBCXX_FLAGS="-nostdinc++ -nostdlib++ -isystem ${LIBCXX_DIR}include/c++/v1 -L${LIBCXX_DIR}lib -Wl,-rpath,${LIBCXX_DIR}lib -lc++ -lc++abi -lpthread -Wno-unused-command-line-argument"
 export MSAN_AND_LIBCXX_FLAGS="${MSAN_FLAGS} ${LIBCXX_FLAGS}"

ci/test/00_setup_env_native_msan.sh

@@ -7,7 +7,7 @@
 export LC_ALL=C.UTF-8
 
 export CI_IMAGE_NAME_TAG="ubuntu:22.04"
-LIBCXX_DIR="${BASE_SCRATCH_DIR}/msan/cxx_build/"
+LIBCXX_DIR="/msan/cxx_build/"
 export MSAN_FLAGS="-fsanitize=memory -fsanitize-memory-track-origins=2 -fno-omit-frame-pointer -g -O1 -fno-optimize-sibling-calls"
 LIBCXX_FLAGS="-nostdinc++ -nostdlib++ -isystem ${LIBCXX_DIR}include/c++/v1 -L${LIBCXX_DIR}lib -Wl,-rpath,${LIBCXX_DIR}lib -lc++ -lc++abi -lpthread -Wno-unused-command-line-argument"
 export MSAN_AND_LIBCXX_FLAGS="${MSAN_FLAGS} ${LIBCXX_FLAGS}"

ci/test/01_base_install.sh

@@ -42,33 +42,35 @@ if [ -n "$PIP_PACKAGES" ]; then
 fi
 
 if [[ ${USE_MEMORY_SANITIZER} == "true" ]]; then
-  git clone --depth=1 https://github.com/llvm/llvm-project -b llvmorg-16.0.6 "${BASE_SCRATCH_DIR}"/msan/llvm-project
-
-  cmake -G Ninja -B "${BASE_SCRATCH_DIR}"/msan/clang_build/ -DLLVM_ENABLE_PROJECTS="clang" \
-                                                            -DCMAKE_BUILD_TYPE=Release \
-                                                            -DLLVM_TARGETS_TO_BUILD=Native \
-                                                            -DLLVM_ENABLE_RUNTIMES="compiler-rt;libcxx;libcxxabi;libunwind" \
-                                                            -S "${BASE_SCRATCH_DIR}"/msan/llvm-project/llvm
-
-  ninja -C "${BASE_SCRATCH_DIR}"/msan/clang_build/ "$MAKEJOBS"
-  ninja -C "${BASE_SCRATCH_DIR}"/msan/clang_build/ install-runtimes
-
-  update-alternatives --install /usr/bin/clang++ clang++ "${BASE_SCRATCH_DIR}"/msan/clang_build/bin/clang++ 100
-  update-alternatives --install /usr/bin/clang clang "${BASE_SCRATCH_DIR}"/msan/clang_build/bin/clang 100
-  update-alternatives --install /usr/bin/llvm-symbolizer llvm-symbolizer "${BASE_SCRATCH_DIR}"/msan/clang_build/bin/llvm-symbolizer 100
-
-  cmake -G Ninja -B "${BASE_SCRATCH_DIR}"/msan/cxx_build/ -DLLVM_ENABLE_RUNTIMES='libcxx;libcxxabi' \
-                                                          -DCMAKE_BUILD_TYPE=Release \
-                                                          -DLLVM_USE_SANITIZER=MemoryWithOrigins \
-                                                          -DCMAKE_C_COMPILER=clang \
-                                                          -DCMAKE_CXX_COMPILER=clang++ \
-                                                          -DLLVM_TARGETS_TO_BUILD=Native \
-                                                          -DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF \
-                                                          -DLIBCXX_ENABLE_DEBUG_MODE=ON \
-                                                          -DLIBCXX_ENABLE_ASSERTIONS=ON \
-                                                          -S "${BASE_SCRATCH_DIR}"/msan/llvm-project/runtimes
-
-  ninja -C "${BASE_SCRATCH_DIR}"/msan/cxx_build/ "$MAKEJOBS"
+  git clone --depth=1 https://github.com/llvm/llvm-project -b llvmorg-16.0.6 /msan/llvm-project
+
+  cmake -G Ninja -B /msan/clang_build/ \
+    -DLLVM_ENABLE_PROJECTS="clang" \
+    -DCMAKE_BUILD_TYPE=Release \
+    -DLLVM_TARGETS_TO_BUILD=Native \
+    -DLLVM_ENABLE_RUNTIMES="compiler-rt;libcxx;libcxxabi;libunwind" \
+    -S /msan/llvm-project/llvm
+
+  ninja -C /msan/clang_build/ "$MAKEJOBS"
+  ninja -C /msan/clang_build/ install-runtimes
+
+  update-alternatives --install /usr/bin/clang++ clang++ /msan/clang_build/bin/clang++ 100
+  update-alternatives --install /usr/bin/clang clang /msan/clang_build/bin/clang 100
+  update-alternatives --install /usr/bin/llvm-symbolizer llvm-symbolizer /msan/clang_build/bin/llvm-symbolizer 100
+
+  cmake -G Ninja -B /msan/cxx_build/ \
+    -DLLVM_ENABLE_RUNTIMES='libcxx;libcxxabi' \
+    -DCMAKE_BUILD_TYPE=Release \
+    -DLLVM_USE_SANITIZER=MemoryWithOrigins \
+    -DCMAKE_C_COMPILER=clang \
+    -DCMAKE_CXX_COMPILER=clang++ \
+    -DLLVM_TARGETS_TO_BUILD=Native \
+    -DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF \
+    -DLIBCXX_ENABLE_DEBUG_MODE=ON \
+    -DLIBCXX_ENABLE_ASSERTIONS=ON \
+    -S /msan/llvm-project/runtimes
+
+  ninja -C /msan/cxx_build/ "$MAKEJOBS"
 fi
 
 if [[ "${RUN_TIDY}" == "true" ]]; then