# Re: \[PATCH 4.19 5/6\] ARM: 8788/1: ftrace: remove old mcount support

- From: Stefan Agner \<stefan@agner.ch\>
- Date: 2022-01-11 21:05:18 
- List: netdev
- Page: https://ratatoskr.run/netdev/2022/01/1630626
- Thread: https://ratatoskr.run/stable/2021/12/1612388/t.md

```text
On 2021-12-20 11:57, Greg KH wrote:
> On Fri, Dec 17, 2021 at 03:41:18PM +0100, Anders Roxell wrote:
>> From: Stefan Agner <stefan@agner.ch>
>>
>> commit d3c61619568c88d48eccd5e74b4f84faa1440652 upstream.
>>
>> Commit cafa0010cd51 ("Raise the minimum required gcc version to 4.6")
>> raised the minimum GCC version to 4.6. Old mcount is only required for
>> GCC versions older than 4.4.0. Hence old mcount support can be dropped
>> too.
>>
>> Signed-off-by: Stefan Agner <stefan@agner.ch>
>> Signed-off-by: Russell King <redacted>
>> Signed-off-by: Anders Roxell <redacted>
> 
> Why is this needed for clang builds in 4.19?

As far as I remember, Clang tripped over this part:

-#ifndef CONFIG_OLD_MCOUNT
-#if (__GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 4))
-#error Ftrace requires CONFIG_FRAME_POINTER=y with GCC older than
4.4.0.
-#endif
-#endif

Since mcount support wasn't required upstream at that point, instead of
fixing it for Clang I just removed it.

--
Stefan
```