diff --git a/Build.md b/Build.md
index 1f245f9..ed647fe 100644
--- a/Build.md
+++ b/Build.md
@@ -16,7 +16,10 @@ git clone --depth=1 --recursive https://github.com/MaskRay/ccls
 cd ccls
 
 # Download "Pre-Built Binaries" from https://releases.llvm.org/download.html
-# and unpack to /path/to/clang+llvm-xxx
+# and unpack to /path/to/clang+llvm-xxx.
+# Do not unpack to a temporary directory, as the clang resource directory is hard-coded
+# into ccls at compile time!
+# See https://github.com/MaskRay/ccls/wiki/FAQ#verify-the-clang-resource-directory-is-correct
 cmake -H. -BRelease -DCMAKE_BUILD_TYPE=Release -DCMAKE_PREFIX_PATH=/path/to/clang+llvm-xxx
 cmake --build Release
 ```