tree 9f02cbdcac4c105dd98b4e92164e65b05a990239
parent 76ad07a4938aac69cb12bfdf52c3bf612c85e4df
author Peter Maydell <peter.maydell@linaro.org> 1365419487 +0100
committer Anthony Liguori <aliguori@us.ibm.com> 1365435524 -0500

configure: Don't fall back to gthread coroutine backend

The gthread coroutine backend is broken and does not produce a working
QEMU; it is only useful for some very limited debugging situations.
Clean up the backend selection logic in configure so that it now runs
"if on windows use windows; else prefer ucontext; else sigaltstack".

To do this we refactor the configure code to separate out "test
whether we have a working ucontext", "pick a default if user didn't
specify" and "validate that user didn't specify something invalid",
rather than having all three of these run together. We also simplify
the Makefile logic so it just links in the backend the configure
script selects.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1365419487-19867-3-git-send-email-peter.maydell@linaro.org
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>