[Bug 18168] New: cmd fails when passing environment variables in a batfile

http://bugs.winehq.org/show_bug.cgi?id=18168

Summary: cmd fails when passing environment variables in a
                    batfile
           Product: Wine
           Version: 1.1.19
          Platform: PC
        OS/Version: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: programs
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]

This is a BDE installaation file:
set SysDir=%windir%\system

if %OS%==Windows_NT (set SysDir=%SysDir%32)

%sysdir%\regsvr32.exe /S bdeinst.dll

While processing the line with "set SysDir=%SysDir%32" cmd fails with the
following error:

Z:\home\vyaltseva3\MDPROJECT>set SysDir=C:\windows\system
Z:\home\vyaltseva3\MDPROJECT>if Windows_NT==Windows_NT 
Z:\home\vyaltseva3\MDPROJECT>set SysDir=C:\windows\system32
wine: Unhandled page fault on read access to 0x00000000 at address 0x7ee214cb
(thread 001c), starting debugger...
Unhandled exception: page fault on read access to 0x00000000 in 32-bit code
(0x7ee214cb).
Register dump:
 CS:0073 SS:007b DS:007b ES:007b FS:0033 GS:003b
 EIP:7ee214cb ESP:00331820 EBP:00331cd8 EFLAGS:00210202(   - 00      - -RI1)
 EAX:00154bf8 EBX:7ee26ff4 ECX:00000000 EDX:00000000
 ESI:00000000 EDI:0000000c
Stack dump:
0x00331820:  00110000 00000000 00004000 00000003
0x00331830:  7ee24e30 ffffffff 00000000 00000000
0x00331840:  00000000 00000000 7ee253f3 7ee66704
0x00331850:  7ee251d0 7ee25410 00331cb0 00331ca4
0x00331860:  00154bf8 00000000 00000006 00000014
0x00331870:  00230c2e 0000001c 00000003 00154bf8
Backtrace:
=>0 0x7ee214cb WCMD_execute+0xcb() in cmd (0x00331cd8)
  1 0x7ee1627b in cmd (+0x1627b) (0x00331d38)
  2 0x7ee16616 WCMD_if+0x186() in cmd (0x00331f78)
  3 0x7ee221ec WCMD_execute+0xdec() in cmd (0x00332438)
  4 0x7ee225ab WCMD_process_commands+0x9b() in cmd (0x00332478)
  5 0x7ee12173 WCMD_batch+0x123() in cmd (0x003364c8)
  6 0x7ee21349 WCMD_run_program+0xba9() in cmd (0x0033f0d8)
  7 0x7ee21777 WCMD_execute+0x377() in cmd (0x0033f598)
  8 0x7ee225ab WCMD_process_commands+0x9b() in cmd (0x0033f5d8)
  9 0x7ee22f6e wmain+0x8de() in cmd (0x0033fee8)
  10 0x7ee23692 in cmd (+0x23692) (0x0033ff08)
  11 0x7b877dc0 in kernel32 (+0x57dc0) (0x0033ffe8)
  12 0xb7f53da7 wine_switch_to_stack+0x17() in libwine.so.1 (0x00000000)
0x7ee214cb WCMD_execute+0xcb in cmd: movzwl     0x0(%ecx,%edx,1),%eax