In the updated patch, I use hash table when looking for up minsyms, but
in a little different way. After currently constructing minsyms are
installed to OBJFILE, there is a hash table built, we can use that one,
instead of maintaining a separate one. That is, after the hash table
of minsyms of OBJFILE is built up, we can iterate all minsyms, if
symbol is _imp_x, look up x in the hash table. If found, modify the
found's type.
Regression tested on i686-pc-mingw32. The following fail is fixed.
FAIL: gdb.base/solib-symbol.exp: foo in libmd