August 29, 2021
https://issues.dlang.org/show_bug.cgi?id=22248

          Issue ID: 22248
           Summary: ImportC: Specify C compiler when multiple options are
                    available
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: ImportC, spec
          Severity: enhancement
          Priority: P1
         Component: dlang.org
          Assignee: nobody@puremagic.com
          Reporter: schveiguy@gmail.com

For instance, on Linux, dmd can link with code built with both gcc and clang (and likely others). If D will compile C code, and there may be differences between the various compilers (e.g. bitfield handling), the ImportC compiler should select a default compiler for that platform.

Obviously, ldc should match llvm, and gdc should match gcc. But DMD doesn't always have an equivalent C compiler.

Optionally, it may be useful (if all the code is going to be inside the front end anyway) to specify an expected compatible compiler.

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