Build fails on clang 3.9, 4 & 5 (not 6)

[helmesjo]

I've created a conan package for aeron. It fails when building with clang (except version 6) with the following error:

aeron-client/src/main/cpp/util/MemoryMappedFile.h:42:50: error: unknown type name 'off_t'
    static ptr_t createNew(const char* filename, off_t offset, size_t length)

PR #315 changed usages of size_t to off_t. Was this really necessary to make it compile for windows?

Any suggestions for a workaround?

[tmontgomery]

Awesome that you've got a conan package for Aeron! Thanks!

Changing to off_t was done more for cleaning up. Don't think it is used for win32 build. off_t is a normal type, though, to have for Linux (and most POSIX) anyway. So, that is quite odd that it isn't finding the type. Could this be an include issue (or some sort of compat flag issue?)

[helmesjo]

You're welcome! :)

Yeah, off_t is apparently found in <sys/types.h>. That header is included in MemoryMappedFile.cpp, but should perhaps then have been included in MemoryMappedFile.h instead, before declaring the class.

Here are the settings & options passed to conan when building the package:

+------------------------+
| Profile                |
|------------------------|
| include(default)       |
|                        |
| [settings]             |
| arch=x86               |
| build_type=Release     |
| compiler=clang         |
| compiler.libcxx=libc++ |
| compiler.version=3.9   |
| [options]              |
| aeron:shared=True      |
| [env]                  |
|                        |
| [build_requires]       |
+------------------------+

[mjpt777]

@tmontgomery how do you feel about moving to a convention that each file can compile on its own with dependencies? If a header has dependencies it includes them. This should address such issues.

[tmontgomery]

We have this somewhat in the C driver. But, yes, some includes should be moved to the headers in the C++ API.