Windows implementation of setjmp/longjmp is done in C:/WINDOWS/system32/ucrtbase.dll. Alas, on arm64, it seems to *always* perform stack unwinding, which crashes from generated code.
By using alternative implementation built in mingw, we avoid doing stack unwinding and this fixes crash when calling longjmp. Signed-off-by: Pierrick Bouvier <pierrick.bouv...@linaro.org> --- include/sysemu/os-win32.h | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h index 5b38c7bd04..84f62d0a17 100644 --- a/include/sysemu/os-win32.h +++ b/include/sysemu/os-win32.h @@ -51,14 +51,28 @@ typedef struct sockaddr_un { extern "C" { #endif -#if defined(_WIN64) +#if defined(__aarch64__) +/* On windows-arm64, setjmp is available in only one variant, and longjmp always + * does stack unwinding. This crash with generated code. + * Thus, we use another implementation of setjmp (not windows one), coming from + * mingw, which never performs stack unwinding. */ +#undef setjmp +#undef longjmp +/* These functions are not declared in setjmp.h because __aarch64__ defines + * setjmp to _setjmpex instead. However, they are still defined in libmingwex.a, + * which gets linked automatically. */ +extern int __mingw_setjmp(jmp_buf); +extern void __attribute__((noreturn)) __mingw_longjmp(jmp_buf, int); +#define setjmp(env) __mingw_setjmp(env) +#define longjmp(env, val) __mingw_longjmp(env, val) +#elif defined(_WIN64) /* On w64, setjmp is implemented by _setjmp which needs a second parameter. * If this parameter is NULL, longjump does no stack unwinding. * That is what we need for QEMU. Passing the value of register rsp (default) * lets longjmp try a stack unwinding which will crash with generated code. */ # undef setjmp # define setjmp(env) _setjmp(env, NULL) -#endif +#endif /* __aarch64__ */ /* QEMU uses sigsetjmp()/siglongjmp() as the portable way to specify * "longjmp and don't touch the signal masks". Since we know that the * savemask parameter will always be zero we can safely define these -- 2.30.2