fix Issue 9650 - __traits(compiles) + mixin

I couldn't minimize test case, but the bug fix is obvious.

The bug had been hiding for a long time, but recent Phobos change (https://github.com/D-Programming-Language/phobos/commit/2a88fea7867f33fd1cf15c2dca7790a3c8aea474) had exposed the bug.

When a mixin expression gets invalid code string, the parsing error had not handled correctly. In such case, it had generated *invalid* AST instead of returning ErrorExp. I guess that the invalid AST would report weird error in later semantic analysis.

I think that both CompileDeclaration and CompileStatement do not have same problem. So they are not changed.
Cast T[] to integral type: deprecation -> error.
refactor libomf
refactor libomf
Fixes Issue 9758 - Emit documented unittest block even if unittest body is empty.
add missing print api to stub version of struct code
Merge pull request #1770 from AndrejMitrovic/Fix9758

Issue 9758 - Emit documented unittest block even if unittest body is empty
fix test case for bug 9713
Merge pull request #1769 from 9rnsr/fix_ddoc

fix test case for bug 9713
fix Issue 9474 - Ddoc'd unittests should work correctly with interspersed version(none)
remove dead got related code
Merge pull request #1774 from braddr/cleanup-got

remove dead got related code
Merge pull request #1772 from braddr/fix-stub

add missing print api to stub version of struct code
Include -devel-HASH(-dirty) in the version string

When not compiled with `make RELEASE=1`, the version string will include
a suffix with the exact version information based on the git hash. Also,
if the current working tree is dirty (it have uncommitted changed) an
extra suffix will be added (-dirty).

When using `make RELEASE=1` only the version information present in the
VERSION file will be used.
Merge pull request #1737 from leandro-lucarella-sociomantic/devel-version

Include -devel-HASH(-dirty) in the version string
remove never-true code
Merge pull request #1600 from braddr/cleanup

Isolate CFseg usage in common code
expose dwarf_regno as a platform specific function
Fix issue 9774 Error message with __error using == on tuple members
Merge pull request #1767 from WalterBright/scanomf

refactor: split libomf.c into libomf.c and scanomf.c