Features/w64

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Host Support for Windows 64 bit

Today, QEMU can be compiled for 32 bit versions of the Windows OS.

The need for 64 bit versions will increase as the number of 64 bit installations grows.

There is also a certain demand for large memory support which is not possible with 32 bit versions of QEMU.

Main problems to solve for 64 bit support

  • Type casts between pointer and integral values must not use (long) or (unsigned long) because pointers are 64 bit while long is only 32 bit.
  • For the same reason, variables and struct members which hold the numeric value of a host address cannot use long or unsigned long.
  • The w64 ABI is currently unsupported.

Status

An experimental version of 64 bit QEMU runs with TCI, but not the x86_64 TCG (ABI problems?). First patches were sent to the mailing list.