Fix up the error processing in VG_(expand_file_name). E.g. giving
--log-file=  on the command line results in the following error:

valgrind: --log-file: filename is emptyBad option: --log-file=

Relatedly, fix the 1st argument to VG_(expand_file_name) in coredump-elf.c.
This should not contain additional verbiage as it is assumed to be an option
name which us used to construct an error message containing

As an aside, this logic in coredump-elf.c seems odd:
If VG_(clo_log_fname_expanded) is not NULL, then it has already been
expanded in main_process_cmd_line_options. Expanding it again would only
make a difference, if the original logfile name contained an environment 
variable whose value contained %q{whatever} thereby referring to a yet
another environment variable. That seems strange.
But I'm not touching it.

git-svn-id: svn:// a5019735-40e9-0310-863c-91ae7b9d1cf9
2 files changed