https://issues.dlang.org/show_bug.cgi?id=17699

          Issue ID: 17699
           Summary: Importing a module that has both modulename.d and
                    modulename/package.d should be an error
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: schveiguy@yahoo.com

This has happened to several people, and can be reproduced easily:

extract dmd 2.074.1
extract dmd 2.075.0 over it.

Write some code that imports std.datetime.

result: linker errors.

What is happening is 2.075 split std.datetime into a std.datetime package. This creates a situation where both std/datetime.d and std/datetime/package.d exist. The compiler imports the former and ignores the latter.

However, the library is built with only the package file, so the symbol mangling is completely different for the new version.

I propose that if the compiler sees such a situation, it should throw an ambiguity error instead of picking one or the other. This would at least prevent such head-scratching errors.

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