This follows the approach we use in ASan and UBSan lit tests to setup
tool options in a portable way, and to provide a nice way to specify
testsuite-wide defaults.
llvm-svn: 246058
include_if_exists=/path/to/sanitizer/options reads flags from the
file if it is present. "%b" in the include file path (for both
variants of the flag) is replaced with the basename of the main
executable.
llvm-svn: 242853
Alexey Samsonov