bugpoint has several options specified as PositionalEatArgs to pass
options through to the underlying tool, e.g. -tool-args. The -help
message suggests the usage is: -tool-args=<string>. However, this is
misleading, because that's not how these arguments work. Rather than taking
a value, the option consumes all positional arguments until the next
recognized option (or all arguments if -- is specified at some point).
To make this slightly clearer, instead print the help as:
-tool-args <string>... - <tool arguments>...
Additionally, add an error if the user attempts to use a PositionalEatArgs
argument with a value, instead of silently ignoring it. Example:
./bin/bugpoint -tool-args=-mpcu=skylake-avx512 bugpoint: for the -tool-args option: This argument does not take a value. Instead, it consumes any positional arguments until the next recognized option.