[Bug 31090] New: Wine overwrites dyld debug information

http://bugs.winehq.org/show_bug.cgi?id=31090

Bug #: 31090
           Summary: Wine overwrites dyld debug information
           Product: Wine
           Version: 1.5.7
          Platform: x86
        OS/Version: Mac OS X
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: loader
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]
    Classification: Unclassified

I've been trying to get windbag --gdb working on OS X. There seem to be
multiple issues, but a major one is that it can't load the debug headers needed
to get information out of the debugged processes.

What happens is that dbghelp/macho_module tries to read memory from the symbol
_dyld_all_image_infos in the target process. Turns out this symbol is always at
the address 0x8fe340e0, at least on my machine.

Looking with vmmap on a running wine process, this address is in an unreadable
mapping:

VM_ALLOCATE            82000000-8d9f0000 [185.9M] ---/rwx SM=NUL

which I traced to

void mmap_init(void)
{
...
    if (base > user_space_limit) reserve_area( user_space_limit, base );
}

before this call the region points to /usr/lib/dyld:
__DATA                 8fe33000-8fe38000 [   20K] rw-/rwx SM=COW  /usr/lib/dyld

but after it is as above.

But I'm afraid I don't know how to fix it. I tried adding

wine_mmap_add_reserved_area( (void*)0x82000000, 0x8ff2c000 - 0x82000000 );

to loader/main.c but it didn't seem to help. So I'm writing this bug report,
hoping someone else is able to fix it.