https://issues.dlang.org/show_bug.cgi?id=24123

          Issue ID: 24123
           Summary: More definitions are needed for ImportC to function on
                    macOS (additions needed for importc.h)
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Mac OS X
            Status: NEW
          Severity: blocker
          Priority: P1
         Component: druntime
          Assignee: nobody@puremagic.com
          Reporter: trnsz@pobox.com

Using DMD ImportC on macOS, most non-trivial programs that use stdio won't function.

Using macOS Intel 13.5, Darwin 22.6.0, Xcde 14.3.1, DMD64 v2.105.0.

Problem is that https://github.com/dlang/dmd/blob/25d2741b86b1060ec43d80dbcc8dc190d5453322/druntime/src/importc.h#L98 is incomplete.

For my application to compile and link, I had to add the following additional lines here in the APPLE section.  I'm sure others will likely be needed, but this was enough for me.

# define __builtin___snprintf_chk(s, c, flag, os, fmt, ...) snprintf(s, c, fmt,
__VA_ARGS__)
# define __builtin___sprintf_chk(s, flag, os, fmt, ...) sprintf(s, fmt,
__VA_ARGS__)
# define __builtin___vsnprintf_chk(s, c, flag, os, fmt, ...) vsnprintf(s, c,
fmt, __VA_ARGS__)
# define __builtin___strlcat_chk(dest, src, x, n) strlcat(dest,src,x)
# define __builtin___strlcpy_chk(dest, src, x, n) strlcpy(dest,src,x)
# define __builtin_object_size

----

I hope this is helpful!

Perhaps this should be another issue, but, it seems one cannot use C11 atomics.

I don't know if this is something that can be worked around, but if you try to use them, you get the following error messages from DMD:

file.c(99): Error: undefined identifier `__c11_atomic_load`
file.c(126): Error: undefined identifier `__c11_atomic_store`
file.c(204): Error: undefined identifier `__c11_atomic_store`
file.c(220): Error: undefined identifier `__c11_atomic_load`
file.c(429): Error: undefined identifier `__c11_atomic_init`

I can work around this for my application, but, as ImportC is supposed to be C11 compliant, I'd hope that C11 atomics can be supported on macOS.

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