Re: Difficulty integrating with Swift/Objective-C

[paul]

I wanted to follow up about another thing:

On 2021-09-05 at 16:03 AEST, quoth paul <paul@inktvis.org>:
> I had some difficulty getting my app to compile against Guile, 
> but i eventually managed to link against a version of Guile 
> installed with Homebrew (guile: stable 3.0.7 (bottled)), however 
> when trying to boot it up i seemed to run into the same issue 
> described by Jeffrey Walton [1].  My app would boot, and as soon 
> as it hit the Guile initialisation calls, it would error out as 
> follows:
>
> allocating JIT code buffer failed: Permission denied
> jit.c:5873: fatal: assertion failed
>
> While the other person seems to imply the problem is with 
> Apple's M1 silicon, i'm actually running an older machine (2.9 
> GHz Dual-Core Intel Core i5, macOS 11.5.2).  I then managed to 
> get further by downloading the Guile release tarball version 
> 3.0.7 and and building with `./configure --enable-jit=no`;>
>
> [...]
>
> 1. https://mail.gnu.org/archive/html/bug-guile/2021-03/msg00012.html

It turned out that the JIT issue was _also_ PEBKAC i am glad to 
report.  Completely by accident i happened upon some settings in 
the Xcode project of my app, under the Target > Signing & 
Capabilities > Hardened Runtime options.  One has to enable the 
following two items:

* Allow execution of JIT-compiled code

* Allow unsigned executable memory

Those two settings correspond to entries in the 
<myapp>.entitlements file as follows:

<dict>
        <key>com.apple.security.cs.allow-jit</key>
        <true/>
        <key>com.apple.security.cs.allow-unsigned-executable-memory</key>
        <true/>
</dict>

Now, the app is able to build and run successfully against the 
Homebrew-packaged version of Guile - super convenient!

I thought i'd post my findings in case someone else hits these 
issues in the future.  Or should i contribute a section to a 
README somewhere, so that folks don't have to laboriously work 
this out for themselves every time?

Cheers,
p.