From: "katei (Yuta Saito)" <noreply@...>
Date: 2022-09-23T18:53:19+00:00
Subject: [ruby-core:110051] [Ruby master Bug#18912] Build failure with Xcode 14 and macOS 13 (Ventura) Beta

Issue #18912 has been updated by katei (Yuta Saito).



From my further debugging, I found that CoreFoundation internally creates NSTaggedPointerString for small strings since macOS 13.

This C code can check a string is represented by tagged pointer in CoreFoundation.

```c
// $ clang -g main.c -framework CoreFoundation
// $ ./a.out # on macOS ~12
// CFStringCreateWithBytesNoCopy("/") =     0x600003d94780 (tagged = NO)
// $ ./a.out # on macOS 13
// CFStringCreateWithBytesNoCopy("/") = 0xab98bd5bc57e5fed (tagged = YES)

#include <CoreFoundation/CFString.h>
#include <stdio.h>

// Ref: https://github.com/apple-oss-distributions/objc4/blob/8701d5672d3fd3cd817aeb84db1077aafe1a1604/runtime/objc-internal.h#L446-L482
#if (TARGET_OS_OSX || TARGET_OS_MACCATALYST) && __x86_64__
# define _OBJC_TAG_MASK 1ULL
#else
# define _OBJC_TAG_MASK 0x8000000000000000ULL
#endif

#define _objc_isTaggedPointer(x) (((uintptr_t)(x)&_OBJC_TAG_MASK) != 0)

int main(void) {
  long len = 1;
  const char *ptr = "/";
  CFStringRef s = CFStringCreateWithBytesNoCopy(
      kCFAllocatorDefault, (const UInt8 *)ptr, len, kCFStringEncodingUTF8,
      FALSE, kCFAllocatorNull);
  printf("CFStringCreateWithBytesNoCopy(\"%s\") = %18p (tagged = %s)\n", ptr, s,
         _objc_isTaggedPointer(s) ? "YES" : "NO");
  return 0;
}
```


In the above reproducible case in #note-12,
1. `Process.daemon(false, true)` performs `chdir("/")`
2. `Dir.pwd` calls `CFStringCreateWithBytesNoCopy` API with `"/"`
3. `CFStringCreateWithBytesNoCopy` returns `NSTaggedPointerString` because `"/"` is small enough to fit in the tagged string.
4. `CFStringCreateMutableCopy` calls `NSMutableString`'s methods based on the tagged string.

So a reduced minimum repro can be:

```ruby
pid = fork { p File.realpath "/" }
Process.waitpid(pid)
```

To avoid Objective-C runtime crash, we need to warm up Objective-C classes internally used in CFString family API by passing small string before `fork()`.

Here is a patch to address it https://github.com/ruby/ruby/pull/6426



----------------------------------------
Bug #18912: Build failure with Xcode 14 and macOS 13 (Ventura) Beta
https://bugs.ruby-lang.org/issues/18912#change-99302

* Author: hsbt (Hiroshi SHIBATA)
* Status: Assigned
* Priority: Normal
* Assignee: hsbt (Hiroshi SHIBATA)
* Backport: 2.7: REQUIRED, 3.0: REQUIRED, 3.1: REQUIRED
----------------------------------------
Today, I tried to build ruby master with macOS 13 (Ventura) Beta. It breaks the build status caused by Xcode 14 beta changes.

TL;DR: We should add `--without=+,bigdecimal --enable-shared` to the `configure` option.

1. Build failed without `--enable-shared`.

I build ruby master without `--enable-shared` option. I got the following error.

```
(snip)
linking shared-object -test-/arith_seq/extract.bundle
Undefined symbols for architecture arm64:
  "_rb_arithmetic_sequence_extract", referenced from:
      _arith_seq_s_extract in extract.o
  "_rb_ary_new_capa", referenced from:
      _arith_seq_s_extract in extract.o
  "_rb_ary_store", referenced from:
      _arith_seq_s_extract in extract.o
  "_rb_define_singleton_method", referenced from:
      _Init_extract in extract.o
  "_rb_path2class", referenced from:
      _Init_extract in extract.o
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
```

@katei says this error affects with `-undefined dynamic_lookup` flags.

2. Build error with bigdecimal

With `--enabled-shared` resolved the first error. But I got the another build failure.

```
compiling bigdecimal.c
In file included from bigdecimal.c:13:
In file included from ./bigdecimal.h:14:
./missing.h:127:1: error: static declaration of 'rb_rational_num' follows non-static declaration
rb_rational_num(VALUE rat)
^
../.././include/ruby/internal/intern/rational.h:128:7: note: previous declaration is here
VALUE rb_rational_num(VALUE rat);
      ^
In file included from bigdecimal.c:13:
In file included from ./bigdecimal.h:14:
(snip)
```

It's affected with `static inline` declaration in missing.h of bigdecimal.

3. test failure with mjit

I could build with `--with-out-ext=+,bigdecimal --enable-share` option. But I also got the test failure with mjit.

```
[215/402] TestMJIT#test_lambda_longjmp = 0.19 s
192) Failure:
TestMJIT#test_lambda_longjmp [/Users/hsbt/Documents/github.com/ruby/ruby/test/ruby/test_mjit.rb:1045]:
Expected 1 times of JIT success, but succeeded 0 times.

script:
"""

fib = lambda do |x|
  return x if x == 0 || x == 1
  fib.call(x-1) + fib.call(x-2)
end
print fib.call(5)

"""


stderr:
"""
Undefined symbols for architecture arm64:
  "_mjit_call_p", referenced from:
      __mjit0 in _ruby_mjit_p39885u0-643ab5.o
      _vm_sendish in _ruby_mjit_p39885u0-643ab5.o
```

I already shared this to @k0kubun .

macOS 13 beta is still development status. I will track this until the official release date.






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