• d-bugmail puremagic.com (35/35) Jun 21 2019 https://issues.dlang.org/show_bug.cgi?id=19991

d-bugmail puremagic.com writes:

https://issues.dlang.org/show_bug.cgi?id=19991

          Issue ID: 19991
           Summary: win32: bad debug line info with unwining code
           Product: D
           Version: D2
          Hardware: x86
                OS: Windows
            Status: NEW
          Keywords: symdeb
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody puremagic.com
          Reporter: r.sagitario gmx.de

Compile this code with debug information for Win32 (i.e. with -m32 or
-m32mscoff):


int mightThrow(int x)
{
        return x;
}

int main()
{
        int x = 3;
        if (x == 0)           // step in debugger
                return 1;     // jumps here
        scope(exit) x = -1;
        mightThrow(1);        // and continues here
        return 0;
}

Stepping over the if statement shows the return statement as the next
instruction, even though the next step continues with the call to mightThrow.

This is caused by the instruction settings the "exception marker" that
remembers the code position for unwinding. It is considered to be part of the
if statement.

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