https://issues.dlang.org/show_bug.cgi?id=24718

--- Comment #1 from Steven Schveighoffer <schveiguy@gmail.com> ---
>From the forum post:
https://forum.dlang.org/post/tpebcqwzdqfkhnlkmbpd@forum.dlang.org

/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/mach/vm_types.h(168):
Error: variable `lib_test.mach_vm_range_recipe_v1_t.range` - no definition of
struct `mach_vm_range`
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/mach/vm_types.h(168):
       see https://dlang.org/spec/struct.html#opaque_struct_unions
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/mach/vm_types.h(168):
       perhaps declare a variable with pointer type `mach_vm_range*` instead

This is actually the error I encountered as well. I wanted to put it in a comment so those looking for the error will find this issue.

I boiled the problem down to this simple reproduction.

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