diff --git a/.ci/build.sh b/.ci/build.sh
index 445b5fbfb..76c714018 100644
--- a/.ci/build.sh
+++ b/.ci/build.sh
@@ -211,7 +211,7 @@ then
 	echo [-] Using MSYSTEM [$MSYSTEM]
 
 	# Point CMake to the toolchain file.
-	cmake_flags_extra="$cmake_flags_extra -D CMAKE_TOOLCHAIN_FILE=\"$cwd/cmake/$toolchain.cmake\""
+	cmake_flags_extra="$cmake_flags_extra -D CMAKE_TOOLCHAIN_FILE=\"cmake/$toolchain.cmake\""
 elif is_mac
 then
 	# macOS lacks nproc, but sysctl can do the same job.