3 Commits

Author	SHA1	Message	Date
Alex Crichton	9c462b84c8	std: Fix linking against signal on Android ... Currently the minimum supported Android version of the standard library is API level 18 (android-18). Back in those days [1] the `signal` function was just an inline wrapper around `bsd_signal`, but starting in API level android-20 the `signal` symbols was introduced [2]. Finally, in android-21 the API `bsd_signal` was removed [3]. Basically this means that if we want to be binary compatible with multiple Android releases (oldest being 18 and newest being 21) then we need to check for both symbols and not actually link against either. This was first discovered in rust-lang/libc#236 with a fix proposed in rust-lang/libc#237. I suspect that we'll want to accept rust-lang/libc#237 so Rust crates at large continue to be compatible with newer releases of Android and crates, like the standard library, that want to opt into older support can continue to do so via similar means. Closes rust-lang/libc#236 [1]: https://chromium.googlesource.com/android_tools/+/20ee6d20/ndk/platforms/android-18/arch-arm/usr/include/signal.h [2]: https://chromium.googlesource.com/android_tools/+/fbd420/ndk_experimental/platforms/android-20/arch-arm/usr/include/signal.h [3]: https://chromium.googlesource.com/android_tools/+/20ee6d/ndk/platforms/android-21/arch-arm/usr/include/signal.h	2016-04-04 21:54:59 -07:00
Alex Crichton	46315184cb	std: Add support for accept4 on Linux ... This is necessary to atomically accept a socket and set the CLOEXEC flag at the same time. Support only appeared in Linux 2.6.28 so we have to dynamically determine which syscall we're supposed to call in this case.	2016-02-05 17:11:02 -08:00
Alex Crichton	1a31e1c09f	std: Add a helper for symbols that may not exist ... Right now we only attempt to call one symbol which my not exist everywhere, __pthread_get_minstack, but this pattern will come up more often as we start to bind newer functionality of systems like Linux. Take a similar strategy as the Windows implementation where we use `dlopen` to lookup whether a symbol exists or not.	2016-02-05 17:11:02 -08:00