Vim build sometimes fails for unknown reason

[ZyX]

While cross-compiling vim for target i686-mingw32 I sometimes encounter errors
   Assembler messages:
   Fatal error: can't create gobj/charset.o: No such file or directory
   Assembler messages:
   Fatal error: can't create gobj/blowfish.o: No such file or directory
   Assembler messages:
   Fatal error: can't create gobj/diff.o: No such file or directory
   Assembler messages:
   Fatal error: can't create gobj/buffer.o: No such file or directory
. These errors does not happen on second run or happen in other place.
What does it mean and how can I fix it?

Build script can be found here:
http://vimpluginloader.hg.sourceforge.net/hgweb/vimpluginloader/dev-
tools/file/60e913d56727/build.zsh

Library versions:
    strawberry perl 5.12.3.0
    python 2.7.2
    ruby 1.9.2
    lua 5.1.4
Make version:
    GNU Make 3.82
    Built for x86_64-pc-linux-gnu
Gcc version:
    i686-mingw32-gcc (Gentoo 4.5.2 p1.1, pie-0.4.5) 4.5.2
Binutils version: 2.21.1

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