From 2e7fe7e79f41e294eeed2f484eeb791284ec48a2 Mon Sep 17 00:00:00 2001
From: Tyler Michael Smith <tyler@neuralmagic.com>
Date: Sat, 28 Sep 2024 23:13:01 -0400
Subject: [PATCH] [Build/CI] Set FETCHCONTENT_BASE_DIR to one location for
 better caching (#8930)

---
 .gitignore     | 1 +
 CMakeLists.txt | 9 +++++++++
 2 files changed, 10 insertions(+)

diff --git a/.gitignore b/.gitignore
index abeaf0a8..5367ece8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -33,6 +33,7 @@ share/python-wheels/
 .installed.cfg
 *.egg
 MANIFEST
+/.deps/
 
 # PyInstaller
 #  Usually these files are written by a python script from a template
diff --git a/CMakeLists.txt b/CMakeLists.txt
index b2fa72d4..e531a410 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -166,7 +166,16 @@ if(NVCC_THREADS AND VLLM_GPU_LANG STREQUAL "CUDA")
   list(APPEND VLLM_GPU_FLAGS "--threads=${NVCC_THREADS}")
 endif()
 
+
+#
+# Use FetchContent for C++ dependencies that are compiled as part of vLLM's build process.
+# Configure it to place files in vllm/.deps, in order to play nicely with sccache.
+#
 include(FetchContent)
+get_filename_component(PROJECT_ROOT_DIR "${CMAKE_CURRENT_SOURCE_DIR}" ABSOLUTE)
+file(MAKE_DIRECTORY "${FETCHCONTENT_BASE_DIR}")
+set(FETCHCONTENT_BASE_DIR "${PROJECT_ROOT_DIR}/.deps")
+message(STATUS "FetchContent base directory: ${FETCHCONTENT_BASE_DIR}")
 
 #
 # Define other extension targets