Clang tool executes cc1 commands in the same process after b4a99a0. It causes increasing memory consumption for compilations where several source files are passed (for C++ application) or several build steps (e.g. for SYCL application we have host, device and integration header step per source file). Memory is not freed for all cc1 commands until end of overall process.
Commit d357add forces clang driver use old behavior until memory issue is fixed