https://issues.dlang.org/show_bug.cgi?id=24708

          Issue ID: 24708
           Summary: _d_assert_msg not weak linkage?
           Product: D
           Version: D2
          Hardware: All
               URL: http://dlang.org/library/druntime/src/core/exception.h
                    tml
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P3
         Component: druntime
          Assignee: nobody@puremagic.com
          Reporter: turkeyman@gmail.com

I tried to supply my own _d_assert_msg function to replace the druntime implementation. Program linked, but it still called the original druntime version.

Not sure why I didn't get a multiple defined symbols error, but regardless, the druntime function should be marked for weak linkage so applications can supply their own implementation.

This principle may apply to a lot of druntime functions...

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