Building OpenSSL with Visual Studio 2010 for x64 / Win64 causes error


Today I was trying to build the latest OpenSSL 1.0.1c with Visual Studio 2010. Following instructions form the INSTALL.W32, I was able to successfully build the 32-bit version. Trying the same with 64-bit (x64) version, again following the official instructions from INSTALL.W64.
To build for Win64/x64:
> perl Configure VC-WIN64A
> ms\do_win64a
> nmake -f ms\ntdll.mak
> cd out32dll
> ..\ms\test

The first line ‘perl Configure VC-WIN64A’ went without any errors:
Configuring for VC-WIN64A
no-ec_nistp_64_gcc_128 [default] OPENSSL_NO_EC_NISTP_64_GCC_128 (skip dir)
no-gmp [default] OPENSSL_NO_GMP (skip dir)
no-jpake [experimental] OPENSSL_NO_JPAKE (skip dir)
no-krb5 [krb5-flavor not specified] OPENSSL_NO_KRB5
no-md2 [default] OPENSSL_NO_MD2 (skip dir)
no-rc5 [default] OPENSSL_NO_RC5 (skip dir)
no-rfc3779 [default] OPENSSL_NO_RFC3779 (skip dir)
no-sctp [default] OPENSSL_NO_SCTP (skip dir)
no-shared [default]
no-store [experimental] OPENSSL_NO_STORE (skip dir)
no-zlib [default]
no-zlib-dynamic [default]
DES_INT used
RC4_CHUNK is unsigned long long
Configured for VC-WIN64A.

The second line ‘ms\do_win64a’ always returned errors:
ml64 -c -Foms\uptable.obj ms\uptable.asm
Microsoft (R) Macro Assembler (x64) Version 10.00.40219.01
Copyright (C) Microsoft Corporation. All rights reserved.

Assembling: ms\uptable.asm
ms\uptable.asm(356) : error A2088:END directive required at end of file
ms\uptable.asm(356) : fatal error A1010:unmatched block nesting : _lazy18

Luckily I found solution in
Translation from Russian:
To prevent this, need to change file ms\do_win64a.bat like this: instead of

perl ms\ masm > ms\uptable.asm
ml64 -c -Foms\uptable.obj ms\uptable.asm


perl ms\ masm > ms\uptable.asm
ml64 -c -Foms\uptable.obj ms\uptable.asm

It seems like race condition to me. Command ‘ping’ just adds a pause between two commands.

Thanks to Белая рысь (cyber_lynx)! Source: