http://www.altera.com/literature/rn/rn_qts_90.pdf
pg. 29:
issue:
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In the Quartus II software versions 7.1 SP1 and later,
you may encounter the following error if you have
McAfee VirusScan 8.0.0 Enterprise Edition installed
during system generation in SOPC Builder or while
doing a build in the Nios II IDE.
4 [main] ? (3920)
C:\altera\80\quartus\bin\cygwin\bin sh.exe: *** fatal error - couldn't
allocate heap, Win32 error 487, base
0x6D0000, top 0x6F0000, reserve_size
126976, allocsize 131072, page_const
4096
3 [main] sh 420 fork: child -1 - died
waiting for longjmp before
initialization, retry 0, exit code
0x100, errno 1
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fix:
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Either temporary disable McAfee VirusScan 8.0.0 or
upgrade to VirusScan 8.5.0i.
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