My question is does musl support ELS-TLS when using dl-open.
>
> According to [1], Rich proposed dropping the initial-exec attribute and
> replacing it with -mtls-dialect=gnu2 eight years ago. Has that happened
> yet? If so, dlopen()ing libGL with musl ought to work.
`initial-exec` are only specified for
__GLIBC__, If musl not predefined macro `
__GLIBC__`
```
#if defined(__GLIBC__)
#define __THREAD_INITIAL_EXEC thread_local __attribute__((tls_model("initial-exec")))
#define REALLY_INITIAL_EXEC
#else
#define __THREAD_INITIAL_EXEC thread_local
#endif
```