diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
index ee546357..a1ef3997 100644
--- a/llvm/CMakeLists.txt
+++ b/llvm/CMakeLists.txt
@@ -73,6 +73,9 @@ if (ENABLE_LLVM)
     -DCMAKE_INSTALL_PREFIX=${CMAKE_BUNDLE_INSTALL_PREFIX}
     -DCMAKE_INSTALL_LIBDIR:PATH=${LIB_DIR}
     -DCMAKE_INSTALL_RPATH=${CMAKE_BUNDLE_INSTALL_PREFIX}/${LIB_DIR}
+    # we don't need LLVM itself to be debuggable.  Prevents .pdb and .ilk bloat.
+    -DCMAKE_CXX_FLAGS_DEBUG="$<$<CONFIG:Debug>:/DEBUG:NONE>"
+    -DCMAKE_EXE_LINKER_FLAGS_DEBUG="$<$<CONFIG:Debug>:/DEBUG:NONE /INCREMENTAL:NO>"
     LOG_CONFIGURE ${EXT_BUILD_QUIET}
     LOG_BUILD ${EXT_BUILD_QUIET}
     LOG_INSTALL ${EXT_BUILD_QUIET}