ffmpeg @4.2.1_1 / x265 @3.2: compile fine but cannot be executed/crash immediately mac os 10.15 catalina / Xcode 11.1

[jonasjonas (Frank Hellenkamp)]

I compiled all my installed port anew on Mac OS Catalina/Xcode 11.1.

2 of the ports don't work anymore/crash when run: ffmpeg and x265.

$ x265
fish: “x265” terminated by signal SIGSEGV (Address boundary error)

$ ffmpeg
fish: “ffmpeg” terminated by signal SIGSEGV (Address boundary error)

The old versions (installed on 10.14) still work fine.

Maybe it could be the problem, that the default compile options where changed.

See: ​https://forums.developer.apple.com/thread/121887

OpenZFS seemed to have worked around this by recompiling with -fno-stack-check: ​https://twitter.com/openzfsonosx/status/1181818389053882369

Unfortunately I have no idea how to try that in macports.

[breiter (Brian Reiter)]

Adding os.major 14 to the x265 portfile allows macports to pull down an x265 binary that does not segfault immediately.

[breiter (Brian Reiter)]

Adding -fno-stack-check to configure.cflags-append in the ffmpeg port file seems to have built me a working ffmpeg.

[rafaeldcsantos (Rafael Santos)]

Same thing happens with mpv.

[ryandesign (Ryan Carsten Schmidt)]

Replying to breiter:

Adding os.major 14 to the x265 portfile allows macports to pull down an x265 binary that does not segfault immediately.

Doing that is not recommended.

[jonasjonas (Frank Hellenkamp)]

The configure.cflags-append -fno-stack-check does seem to work with ffmpeg and with mpv. x256 still does crash with “x265” terminated by signal SIGSEGV (Address boundary error).

[kencu (Ken)]

x256 probably needs the -fno-stack-check fix too, then.

[jonasjonas (Frank Hellenkamp)]

I tried that with x256, but with no success

[thenickdude (Nicholas Sherlock)]

This bug is being tracked by ffmpeg too:

​https://trac.ffmpeg.org/ticket/8073

Analysis by zwaldowski:

"It seems the 10.15 toolchain turns on "-fstack-check" by default for Clang, like some Linux distributions do. [...] Accordingly, adding "-fno-stack-check" to "CFLAGS" - f.ex., by '--extra-cflags="-fno-stack-check"' when configuring works around the problem and builds a functioning FFMPEG."

[breiter (Brian Reiter)]

I added compiler.whitelist macports-clang-8.0 to the Portfile for x265 and that fixes it.

[cjones051073 (Chris Jones)]

Setting a compiler whitelist like that is not recommended. Instead please try just black listing the Xcode 11 clang version.

[Chris Jones <jonesc@…>]

In 2de6959b098cb95883863a2cf46575dfcf4c211c/macports-ports (master):

x265: Blacklist clang > 1099 for Xcode 11 'stack-check' issues
Closes: #59246

[breiter (Brian Reiter)]

The patch above only corrects x265. It does not fix ffmpeg which neads configure.cflags-append -fno-stack-check to be fixed.