• via Digitalmars-d-bugs (48/48) Nov 08 2015 https://issues.dlang.org/show_bug.cgi?id=15302

via Digitalmars-d-bugs <digitalmars-d-bugs puremagic.com> writes:

https://issues.dlang.org/show_bug.cgi?id=15302

          Issue ID: 15302
           Summary: DMD -O optimizing out meaningful code
           Product: D
           Version: D2
          Hardware: x86
                OS: All
            Status: NEW
          Severity: major
          Priority: P1
         Component: dmd
          Assignee: nobody puremagic.com
          Reporter: ketmar ketmar.no-ip.org

compiling the following code with "dmd -O" leading to failed assert. seems that
dmd optimized out "lineNumber++;", failing to see that it is used in "catch"
part.

===

class XException : Exception {
  this (string msg, size_t lineNumber, string file=__FILE__, size_t
line=__LINE__, Throwable next=null) pure nothrow  safe {
    super(msg, file, line, next);
    _lineNumber = lineNumber;
  }
   nogc  safe size_t lineNumber() const nothrow {
        return _lineNumber;
    }
  private:
  size_t _lineNumber;
}


void foo (string[] lines) {
  size_t lineNumber = 0;
  try {
    foreach (line; lines) {
      lineNumber++;
      if (line == "Line3") throw new Exception("!");
    }
  } catch (Exception e) {
    throw new XException(e.msg, lineNumber, e.file, e.line, e.next);
  }
}


void main () {
  try {
    foo(["Line", "AnotherLine", "Line3"]);
  } catch (XException e) {
    assert(e.lineNumber == 3);
  }
}

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