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.bouvier@linaro.org>
---
 include/sysemu/os-win32.h | 25 +++++++++++++++++++++++--
 meson.build               | 24 ++++++++++++++++++++++++
 2 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h
index 5b38c7bd04..1f6c141d39 100644
--- a/include/sysemu/os-win32.h
+++ b/include/sysemu/os-win32.h
@@ -51,14 +51,35 @@ typedef struct sockaddr_un {
 extern "C" {
 #endif
 
-#if defined(_WIN64)
+#if defined(__aarch64__)
+#ifndef CONFIG_MINGW64_HAS_SETJMP_LONGJMP
+#error mingw must provide setjmp/longjmp for windows-arm64
+#endif
+/*
+ * 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
diff --git a/meson.build b/meson.build
index 4ba3bf3431..e968ed9e7a 100644
--- a/meson.build
+++ b/meson.build
@@ -2450,6 +2450,30 @@ if targetos == 'windows'
     }''', name: '_lock_file and _unlock_file'))
 endif
 
+if targetos == 'windows'
+  mingw_has_setjmp_longjmp = cc.links('''
+    #include <setjmp.h>
+    int main(void) {
+      /*
+       * These functions are not available in setjmp header, but may be
+       * available at link time, from libmingwex.a.
+       */
+      extern int __mingw_setjmp(jmp_buf);
+      extern void __attribute__((noreturn)) __mingw_longjmp(jmp_buf, int);
+      jmp_buf env;
+      __mingw_setjmp(env);
+      __mingw_longjmp(env, 0);
+    }
+  ''', name: 'mingw setjmp and longjmp')
+
+  config_host_data.set('CONFIG_MINGW64_HAS_SETJMP_LONGJMP',
+                       mingw_has_setjmp_longjmp)
+
+  if cpu == 'aarch64' and not mingw_has_setjmp_longjmp
+    error('mingw must provide setjmp/longjmp for windows-arm64')
+  endif
+endif
+
 ########################
 # Target configuration #
 ########################
-- 
2.30.2

Acked-by: Richard Henderson <richard.henderson@linaro.org>

On 2/20/23 12:12, Pierrick Bouvier wrote:
> 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.bouvier@linaro.org>
> ---
>   include/sysemu/os-win32.h | 25 +++++++++++++++++++++++--
>   meson.build               | 24 ++++++++++++++++++++++++
>   2 files changed, 47 insertions(+), 2 deletions(-)
> 
> diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h
> index 5b38c7bd04..1f6c141d39 100644
> --- a/include/sysemu/os-win32.h
> +++ b/include/sysemu/os-win32.h
> @@ -51,14 +51,35 @@ typedef struct sockaddr_un {
>   extern "C" {
>   #endif
>   
> -#if defined(_WIN64)
> +#if defined(__aarch64__)
> +#ifndef CONFIG_MINGW64_HAS_SETJMP_LONGJMP
> +#error mingw must provide setjmp/longjmp for windows-arm64
> +#endif
> +/*
> + * 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
> diff --git a/meson.build b/meson.build
> index 4ba3bf3431..e968ed9e7a 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -2450,6 +2450,30 @@ if targetos == 'windows'
>       }''', name: '_lock_file and _unlock_file'))
>   endif
>   
> +if targetos == 'windows'
> +  mingw_has_setjmp_longjmp = cc.links('''
> +    #include <setjmp.h>
> +    int main(void) {
> +      /*
> +       * These functions are not available in setjmp header, but may be
> +       * available at link time, from libmingwex.a.
> +       */
> +      extern int __mingw_setjmp(jmp_buf);
> +      extern void __attribute__((noreturn)) __mingw_longjmp(jmp_buf, int);
> +      jmp_buf env;
> +      __mingw_setjmp(env);
> +      __mingw_longjmp(env, 0);
> +    }
> +  ''', name: 'mingw setjmp and longjmp')
> +
> +  config_host_data.set('CONFIG_MINGW64_HAS_SETJMP_LONGJMP',
> +                       mingw_has_setjmp_longjmp)
> +
> +  if cpu == 'aarch64' and not mingw_has_setjmp_longjmp
> +    error('mingw must provide setjmp/longjmp for windows-arm64')
> +  endif
> +endif
> +
>   ########################
>   # Target configuration #
>   ########################

@Philippe Mathieu-Daudé, is that version satisfying for you, regarding 
your initial comments about setjmp/longjmp detection in meson?

I can integrate more changes if needed.

Thanks,
Pierrick

On 2/20/23 16:16, Pierrick Bouvier wrote:
> Acked-by: Richard Henderson <richard.henderson@linaro.org>
> 
> On 2/20/23 12:12, Pierrick Bouvier wrote:
>> 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.bouvier@linaro.org>
>> ---
>>    include/sysemu/os-win32.h | 25 +++++++++++++++++++++++--
>>    meson.build               | 24 ++++++++++++++++++++++++
>>    2 files changed, 47 insertions(+), 2 deletions(-)
>>
>> diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h
>> index 5b38c7bd04..1f6c141d39 100644
>> --- a/include/sysemu/os-win32.h
>> +++ b/include/sysemu/os-win32.h
>> @@ -51,14 +51,35 @@ typedef struct sockaddr_un {
>>    extern "C" {
>>    #endif
>>    
>> -#if defined(_WIN64)
>> +#if defined(__aarch64__)
>> +#ifndef CONFIG_MINGW64_HAS_SETJMP_LONGJMP
>> +#error mingw must provide setjmp/longjmp for windows-arm64
>> +#endif
>> +/*
>> + * 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
>> diff --git a/meson.build b/meson.build
>> index 4ba3bf3431..e968ed9e7a 100644
>> --- a/meson.build
>> +++ b/meson.build
>> @@ -2450,6 +2450,30 @@ if targetos == 'windows'
>>        }''', name: '_lock_file and _unlock_file'))
>>    endif
>>    
>> +if targetos == 'windows'
>> +  mingw_has_setjmp_longjmp = cc.links('''
>> +    #include <setjmp.h>
>> +    int main(void) {
>> +      /*
>> +       * These functions are not available in setjmp header, but may be
>> +       * available at link time, from libmingwex.a.
>> +       */
>> +      extern int __mingw_setjmp(jmp_buf);
>> +      extern void __attribute__((noreturn)) __mingw_longjmp(jmp_buf, int);
>> +      jmp_buf env;
>> +      __mingw_setjmp(env);
>> +      __mingw_longjmp(env, 0);
>> +    }
>> +  ''', name: 'mingw setjmp and longjmp')
>> +
>> +  config_host_data.set('CONFIG_MINGW64_HAS_SETJMP_LONGJMP',
>> +                       mingw_has_setjmp_longjmp)
>> +
>> +  if cpu == 'aarch64' and not mingw_has_setjmp_longjmp
>> +    error('mingw must provide setjmp/longjmp for windows-arm64')
>> +  endif
>> +endif
>> +
>>    ########################
>>    # Target configuration #
>>    ########################

On 21/2/23 10:47, Pierrick Bouvier wrote:
> @Philippe Mathieu-Daudé, is that version satisfying for you, regarding 
> your initial comments about setjmp/longjmp detection in meson?

Yes, the meson check is what I had in mind.

> I can integrate more changes if needed.
> 
> Thanks,
> Pierrick
> 
> On 2/20/23 16:16, Pierrick Bouvier wrote:
>> Acked-by: Richard Henderson <richard.henderson@linaro.org>
>>
>> On 2/20/23 12:12, Pierrick Bouvier wrote:
>>> 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.bouvier@linaro.org>
>>> ---
>>>    include/sysemu/os-win32.h | 25 +++++++++++++++++++++++--
>>>    meson.build               | 24 ++++++++++++++++++++++++
>>>    2 files changed, 47 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h
>>> index 5b38c7bd04..1f6c141d39 100644
>>> --- a/include/sysemu/os-win32.h
>>> +++ b/include/sysemu/os-win32.h
>>> @@ -51,14 +51,35 @@ typedef struct sockaddr_un {
>>>    extern "C" {
>>>    #endif
>>> -#if defined(_WIN64)
>>> +#if defined(__aarch64__)
>>> +#ifndef CONFIG_MINGW64_HAS_SETJMP_LONGJMP
>>> +#error mingw must provide setjmp/longjmp for windows-arm64

Per the meson error [*], this now seems impossible, thus we can
simply drop the CONFIG_MINGW64_HAS_SETJMP_LONGJMP definition?

>>> +#endif
>>> +/*
>>> + * 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__ */

This comment doesn't seem accurate. Maybe "64-bit"?

>>>    /* 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
>>> diff --git a/meson.build b/meson.build
>>> index 4ba3bf3431..e968ed9e7a 100644
>>> --- a/meson.build
>>> +++ b/meson.build
>>> @@ -2450,6 +2450,30 @@ if targetos == 'windows'
>>>        }''', name: '_lock_file and _unlock_file'))
>>>    endif
>>> +if targetos == 'windows'
>>> +  mingw_has_setjmp_longjmp = cc.links('''
>>> +    #include <setjmp.h>
>>> +    int main(void) {
>>> +      /*
>>> +       * These functions are not available in setjmp header, but may be
>>> +       * available at link time, from libmingwex.a.
>>> +       */
>>> +      extern int __mingw_setjmp(jmp_buf);
>>> +      extern void __attribute__((noreturn)) __mingw_longjmp(jmp_buf, 
>>> int);
>>> +      jmp_buf env;
>>> +      __mingw_setjmp(env);
>>> +      __mingw_longjmp(env, 0);
>>> +    }
>>> +  ''', name: 'mingw setjmp and longjmp')
>>> +
>>> +  config_host_data.set('CONFIG_MINGW64_HAS_SETJMP_LONGJMP',
>>> +                       mingw_has_setjmp_longjmp)
>>> +
>>> +  if cpu == 'aarch64' and not mingw_has_setjmp_longjmp
>>> +    error('mingw must provide setjmp/longjmp for windows-arm64')

(This is the [*] error I mentioned earlier).

>>> +  endif
>>> +endif
>>> +
>>>    ########################
>>>    # Target configuration #
>>>    ########################

On 2/21/23 11:33, Philippe Mathieu-Daudé wrote:
> On 21/2/23 10:47, Pierrick Bouvier wrote:
>> @Philippe Mathieu-Daudé, is that version satisfying for you, regarding
>> your initial comments about setjmp/longjmp detection in meson?
> 
> Yes, the meson check is what I had in mind.
> 
>> I can integrate more changes if needed.
>>
>> Thanks,
>> Pierrick
>>
>> On 2/20/23 16:16, Pierrick Bouvier wrote:
>>> Acked-by: Richard Henderson <richard.henderson@linaro.org>
>>>
>>> On 2/20/23 12:12, Pierrick Bouvier wrote:
>>>> 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.bouvier@linaro.org>
>>>> ---
>>>>     include/sysemu/os-win32.h | 25 +++++++++++++++++++++++--
>>>>     meson.build               | 24 ++++++++++++++++++++++++
>>>>     2 files changed, 47 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h
>>>> index 5b38c7bd04..1f6c141d39 100644
>>>> --- a/include/sysemu/os-win32.h
>>>> +++ b/include/sysemu/os-win32.h
>>>> @@ -51,14 +51,35 @@ typedef struct sockaddr_un {
>>>>     extern "C" {
>>>>     #endif
>>>> -#if defined(_WIN64)
>>>> +#if defined(__aarch64__)
>>>> +#ifndef CONFIG_MINGW64_HAS_SETJMP_LONGJMP
>>>> +#error mingw must provide setjmp/longjmp for windows-arm64
> 
> Per the meson error [*], this now seems impossible, thus we can
> simply drop the CONFIG_MINGW64_HAS_SETJMP_LONGJMP definition?
>

I think it's redundant too.

>>>> +#endif
>>>> +/*
>>>> + * 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__ */
> 
> This comment doesn't seem accurate. Maybe "64-bit"?
> 

I'd like to use windows-x64. IMHO,  it's clearer and on par with 
windows-arm64. But I know some people don't like x64 nomenclature.

Alas, several projects are using w32 and w64 names, and there is no 
consensus yet on how win-arm64 should be named.

>>>>     /* 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
>>>> diff --git a/meson.build b/meson.build
>>>> index 4ba3bf3431..e968ed9e7a 100644
>>>> --- a/meson.build
>>>> +++ b/meson.build
>>>> @@ -2450,6 +2450,30 @@ if targetos == 'windows'
>>>>         }''', name: '_lock_file and _unlock_file'))
>>>>     endif
>>>> +if targetos == 'windows'
>>>> +  mingw_has_setjmp_longjmp = cc.links('''
>>>> +    #include <setjmp.h>
>>>> +    int main(void) {
>>>> +      /*
>>>> +       * These functions are not available in setjmp header, but may be
>>>> +       * available at link time, from libmingwex.a.
>>>> +       */
>>>> +      extern int __mingw_setjmp(jmp_buf);
>>>> +      extern void __attribute__((noreturn)) __mingw_longjmp(jmp_buf,
>>>> int);
>>>> +      jmp_buf env;
>>>> +      __mingw_setjmp(env);
>>>> +      __mingw_longjmp(env, 0);
>>>> +    }
>>>> +  ''', name: 'mingw setjmp and longjmp')
>>>> +
>>>> +  config_host_data.set('CONFIG_MINGW64_HAS_SETJMP_LONGJMP',
>>>> +                       mingw_has_setjmp_longjmp)
>>>> +
>>>> +  if cpu == 'aarch64' and not mingw_has_setjmp_longjmp
>>>> +    error('mingw must provide setjmp/longjmp for windows-arm64')
> 
> (This is the [*] error I mentioned earlier).
> 
>>>> +  endif
>>>> +endif
>>>> +
>>>>     ########################
>>>>     # Target configuration #
>>>>     ########################
> 

On 21/2/23 14:16, Pierrick Bouvier wrote:
> On 2/21/23 11:33, Philippe Mathieu-Daudé wrote:
>> On 21/2/23 10:47, Pierrick Bouvier wrote:
>>> @Philippe Mathieu-Daudé, is that version satisfying for you, regarding
>>> your initial comments about setjmp/longjmp detection in meson?
>>
>> Yes, the meson check is what I had in mind.
>>
>>> I can integrate more changes if needed.
>>>
>>> Thanks,
>>> Pierrick
>>>
>>> On 2/20/23 16:16, Pierrick Bouvier wrote:
>>>> Acked-by: Richard Henderson <richard.henderson@linaro.org>
>>>>
>>>> On 2/20/23 12:12, Pierrick Bouvier wrote:
>>>>> 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.bouvier@linaro.org>
>>>>> ---
>>>>>     include/sysemu/os-win32.h | 25 +++++++++++++++++++++++--
>>>>>     meson.build               | 24 ++++++++++++++++++++++++
>>>>>     2 files changed, 47 insertions(+), 2 deletions(-)


>>>>> -#if defined(_WIN64)
>>>>> +#if defined(__aarch64__)
>>>>> +#ifndef CONFIG_MINGW64_HAS_SETJMP_LONGJMP
>>>>> +#error mingw must provide setjmp/longjmp for windows-arm64
>>
>> Per the meson error [*], this now seems impossible, thus we can
>> simply drop the CONFIG_MINGW64_HAS_SETJMP_LONGJMP definition?
>>
> 
> I think it's redundant too.

>>>>> -#endif
>>>>> +#endif /* __aarch64__ */
>>
>> This comment doesn't seem accurate. Maybe "64-bit"?
>>
> 
> I'd like to use windows-x64. IMHO,  it's clearer and on par with 
> windows-arm64. But I know some people don't like x64 nomenclature.

Fine by me :)