* Revert all emscripten musl changes

* Update musl to 1.1.5

* Reapply emscripten patches

* Fix up libs to partially compile

* Revert emscripten musl include folder

* Update musl include folder to 1.1.5

* Reapply emscripten libc include changes

* Get compiling again!

* Restore alltypes.h to have emscripten-specific changes

alltypes.h is autogenerated, and we've since overridden the types

Longer-term, we should figure out a way to either autogenerate the types
to match what emscripten expects, or change emscripten's expectation to
support musl's assumptions. Probably worth including with merging the
asm&wasm ABIs.

* Update expected langinfo test output for fixes in upstream musl

* Canonicalize nans in hyperbolic test

Nans are now printed out with their sign if negative. Asm and wasm treat
these differently, so canonicalize how they print.

* Tweak how musl forwards syscalls to emscripten

Before: pass all syscall args as varargs, args are int32
After: cast all syscall args to int32, pass as varargs
This fixes and prevents aliasing issues, and is more consistent with
other architectures

* Change __syscall to syscall in isatty to set errno

POSIX specifies that isatty sets errno in the case that it fails.
__syscall doesn't set errno, and syscall does.

* Update struct_info again

* Always allocate pthread_self, even in the stub

* sys_open should call __syscall_ret

* Fix up pthread js for optimized code (remove __asm: true)

* Canonicalize more nans in testsuite

* Re-set expected langinfo output

* Update align_moar expected addresses

* Disable assert in wasm_backend llseek syscall

* Update now-passing wasm_backend tests

* Update other.test_locale to non-stub setlocale

* Fix compiling with -s USE_PTHREADS=1

* Initialize __pthread_self() when using pthread_stub

* Canonicalize nans for test_zerodiv

* Update count of globals in test_dlfcn_self

* Rework how we initialize pthread_self for non-threaded applications

* Prefer 'EMSCRIPTEN_START_FUNCS' in test_memorygrowth, because 'var TOTAL_MEMORY' can move around

* Now that CURRENT_LOCALE isn't reading off NULL, test_langinfo should expect ASCII

* Re-disable test_demangle_stacks - was spuriously passing earlier

* Explicitly pass 0 as the high bits for SYS__llseek

* Enable v8 for test_readdir now that it supports printErr

* Only use __syscall_emscripten if __EMSCRIPTEN__ is defined

* Move O_LARGEFILE as default back to libc

* libc #if to #ifdef

* Rename pthread import funcs to not rely on alias

* Consistently reference pthread_setcancelstate by alias in libc

* Stub out fcntl64 for NO_FILESYSTEM case

* Update emscripten-specific pthread struct fields

* Consistently reference pthread_testcancel by alias in libc

* Stub out SYS_rt_sigqueueinfo syscall

* Stub out SYS_sendmmsg syscall

* Stub out SYS_recvmmsg syscall

* Revert "Consistently reference pthread_testcancel by alias in libc"

This reverts commit 43563a5b141a47d4a7aa7e48c059ed0e98597fbb.

* Revert "Consistently reference pthread_setcancelstate by alias in libc"

This reverts commit 2ca2eded8a0d50bb3847cda0a99c900532f6937b.

* Correctly fix unresolved symbol: __pthread_setcancelstate

* Update library_pthread.c pthread_testcancel to match musl's expectations

* test_strftime.c -> test_strftime.cpp

* library_pthread_stub pthread_exit should call exit, not nothing

* TEMP: init pthread_self->locale with pthreads enabled

* Initialize pthread global data from libc in JS

* Move _b_lock and _b_waiters back to not emscripten-only

* Remove untrue __asm annotation from threaded pthread_self, make stub pthread_self non-asm

* Remove old unneeded pthread init exported functions

* Move pthread_self in stub case to libc C code

* Move emscripten_pthread initialization to its own file, out from locale_map.c

* Statically allocate the pthread struct and not just a pointer in the stub case

* Remove commented-out test args

* Remove misleading __asm annotation for _register_pthread_ptr

* Do module-side pthread initialization in-module

* Don't cast away volatile when calling emscripten_futex_wake in __wake

* Expose libc struct to emscripten, use that for non-main pthread initialization

* Re-add pthread_impl.h import to library_pthread.c

* Update align_moar alignment post-rebase

* Update emscripten header include in libc.c

* Remove obsolete locale preallocating code in newlocale

We previously statically allocated a single locale in the event that
we needed to dynamically allocate one during startup. musl changed their
implementation to statically allocate C_LOCALE and UTF8_LOCALE, so we
already get that behavior.
In addition this was causing invalid locales to get allocated instead of
returning NULL, because the preceding logic changed. That was caught by
other.test_locale_wrong

* Update test_llvm_lto

* Bump version to 1.37.5