我在MacOS Tahoe（26.3.1（a））。我有一个需要msgpack（1.4.2）的Ruby项目。

很遗憾，当我运行 bundle install 时，看到：

Fetching msgpack 1.4.2
Installing msgpack 1.4.2 with native extensions
Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

[...]

compiling buffer.c
buffer.c:38:16: warning: '(' and '{' tokens introducing statement expression appear in
different macro expansion contexts [-Wcompound-token-split-by-macro]
   38 |     s_uminus = rb_intern("-@");
      |                ^~~~~~~~~~~~~~~

[...]

buffer_class.c:261:17: error: incompatible function pointer types passing 'VALUE (VALUE)'
(aka 'unsigned long (unsigned long)') to parameter of type 'VALUE (*)(VALUE, VALUE)' (aka
'unsigned long (*)(unsigned long, unsigned long)') [-Wincompatible-function-pointer-types]
  261 |                 read_until_eof_error, (VALUE)(void*) args,
      |                 ^~~~~~~~~~~~~~~~~~~~

[...]

An error occurred while installing msgpack (1.4.2), and Bundler cannot continue.

完整的错误追踪信息很长，所以我只包含了最相关的信息（如果SO支持 <details> 就好了！）。

解决方案

受到这些 similar questions 的启发，以及 this blog post，我设法通过抑制导致安装出错的特定C 警告来完成这个gem的安装：

gem install msgpack -v 1.4.2 --source 'https://rubygems.org/' -- --with-cflags="-Wno-compound-token-split-by-macro -Wno-incompatible-function-pointer-types"

请注意，上述错误输出中的警告ID是通过 -Wno-* 标志引用的。