When building SpiderMonkey for Linux/aarch64, the following build error occurs. 0:03.50B /hg/mozilla-central/js/src/threading/posix/Mutex.cpp:43:3: error: static assertion failed: platformData_ is too small 0:03.50B static_assert(sizeof(platformData_) >= sizeof(PlatformData), 0:03.50B ^ 0:03.50B 0:03.50B In the directory /hg/mozilla-central/obj-aarch64-linux-gnu/js/src 0:03.50B The following command failed to execute properly: 0:03.50B /usr/bin/ccache aarch64-linux-gnu-g++ -o Mutex.o -c -I/hg/mozilla-central/obj-aarch64-linux-gnu/dist/system_wrappers -include /hg/mozilla-central/config/gcc_hidden.h -DNDEBUG=1 -DTRIMMED=1 -DENABLE_BINARYDATA -DENABLE_SIMD -DENABLE_SHARED_ARRAY_BUFFER -DEXPORT_JS_API -DJS_HAS_CTYPES -DDLL_PREFIX="lib" -DDLL_SUFFIX=".so" -DFFI_BUILDING -I/hg/mozilla-central/js/src -I/hg/mozilla-central/obj-aarch64-linux-gnu/js/src -I/hg/mozilla-central/obj-aarch64-linux-gnu/js/src/ctypes/libffi/include -I/hg/mozilla-central/intl/icu/source/common -I/hg/mozilla-central/intl/icu/source/i18n -I/hg/mozilla-central/obj-aarch64-linux-gnu/dist/include -I/hg/mozilla-central/obj-aarch64-linux-gnu/dist/include/nspr -fPIC -DMOZILLA_CLIENT -include /hg/mozilla-central/obj-aarch64-linux-gnu/js/src/js-confdefs.h -MD -MP -MF .deps/Mutex.o.pp -Wall -Wc++11-compat -Wempty-body -Wignored-qualifiers -Woverloaded-virtual -Wpointer-arith -Wsign-compare -Wtype-limits -Wwrite-strings -Wunreachable-code -Wno-invalid-offsetof -Wno-error=maybe-uninitialized -Wno-error=deprecated-declarations -Wno-error=array-bounds -fno-rtti -fno-exceptions -fno-math-errno -std=gnu++0x -pthread -pipe -g -freorder-blocks -O3 -fomit-frame-pointer /hg/mozilla-central/js/src/threading/posix/Mutex.cpp 0:03.50B /hg/mozilla-central/config/rules.mk:963: recipe for target 'Mutex.o' failed When I look bits/pthreadtypes.h on Linux/aarch64 (Ubuntu 15.10), sizeof(pthread_mutex_t) is the following. ... #define __SIZEOF_PTHREAD_MUTEX_T 48 ...

Thanks for the heads up! This should fix it until we can make HAVE_PTHREADS available to spidermonkey.

Nick fixed this implicitly when he added a move constructor in bug 1257019. The definition are all using the pthread_mutex_t defined in <pthreads.h>. Sorry I let this drop off my radar; please re-open if the code on tip does not work for some reason.