[Issue 11028] Step over repeats lines while debugging

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=11028

Iain Buclaw <ibuclaw at gdcproject.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ibuclaw at gdcproject.org

--- Comment #3 from Iain Buclaw <ibuclaw at gdcproject.org> ---
I'd point the finger at the tool used to create PDB information from DWARF
emitted from GDC.

However, especially over the last couple of months at least, there have been a
few notable improvements to how data types and modules are represented in
DWARF.  But I have never had problems stepping through functions in gdb.

Certain things that could be of cause (off the top of my head):

- Sugary syntax for complex operations.  eg:  a[] += b[] + c[];  Where the
array operation call is an artificial (compiler generated) function with no
source/line location.  If the artificial attribute isn't reflected in PDB, then
you may see the step pointer remain in the same location until the array
operation has exited.

- invariant() function called before entering body{}.  If all DWARF information
is stripped from libdruntime, then you may see this as an extra step required
to get into a function.  However the line information for the invariant call
should be the same as the line where the body starts.

- Function call has multiple side effects to evaluate before entering.  If it's
a compiler generated side effect (internal use of creating temporaries) the
debugger should just skip over them.  If it's user code, stepping through each
side effect should be as you'd expect - a().b() -> enter a() then b();


As for Martins comment.  I've only seen jumping around in the debugger when you
compile with optimisations (delayed initialisation until variable *actually*
used, etc).

--