emacs @27.1_2+x11: dyld: lazy symbol binding failed: Symbol not found: _aligned_alloc

[texas-swift (Spencer Swift)]

Hello,

I have so far been unable to build any version of Emacs 27 +x11. I keep getting this message during bootstrap build:

:info:build ./temacs --batch  -l loadup --temacs=pbootstrap
:info:build dyld: lazy symbol binding failed: Symbol not found: _aligned_alloc
:info:build   Referenced from: /opt/local/var/macports/build/_opt_local_var_mac\
ports_sources_rsync.macports.org_macports_release_tarballs_ports_editors_emacs/\
emacs/work/emacs-27.1/src/./temacs
:info:build   Expected in: /usr/lib/libSystem.B.dylib

I can successfully build emacs 27.1_2 W/O x11, but I am a heavy X11 user and prefer that variant. I have also successfully built emacs 26+x11.

macOS 10.14.6 Mojave
Xcode 11.3.1

[texas-swift (Spencer Swift)]

emacs@27.1_2+x11 build log

[ryandesign (Ryan Carsten Schmidt)]

There are several other reports of this problem by searching Google.

Here is the upstream bug report, I think: ​https://debbugs.gnu.org/cgi/bugreport.cgi?bug=36172

The problem occurs because Xcode 11 has the macOS 10.15 SDK. Aligned alloc was apparently introduced in 10.15 and the emacs configure script erroneously takes it presence in the SDK as an indication that it can be used at runtime on 10.14, which it cannot. The developers of emacs appear to be unaware of how macOS SDKs work.

You could avoid the problem by downgrading to Xcode 10 and the Xcode 10 version of the command line tools.

[texas-swift (Spencer Swift)]

Okay. I did Google, but guess I didn't comprehend the Xcode downgrade step.

Thanks,

[barracuda156]

Replying to ryandesign:

The problem occurs because Xcode 11 has the macOS 10.15 SDK. Aligned alloc was apparently introduced in 10.15 and the emacs configure script erroneously takes it presence in the SDK as an indication that it can be used at runtime on 10.14, which it cannot. The developers of emacs appear to be unaware of how macOS SDKs work.

I got this error now when building algol68g on 10.6:

Undefined symbols:
  "_aligned_alloc", referenced from:
      _a68_alloc in a68g-mem.o
ld: symbol(s) not found
collect2: ld returned 1 exit status