Re: Adds dimension stencil command to correct with-dimension (issue 12957047)

[k-ohara5a5a]

https://codereview.appspot.com/12957047/diff/88001/lily/stencil-integral.cc
File lily/stencil-integral.cc (right):

https://codereview.appspot.com/12957047/diff/88001/lily/stencil-integral.cc#newcode917
lily/stencil-integral.cc:917: }
My best guess for the cause of the extra memory, showing in the `make
check` profile output, is this loop written as tail recursion:

stencil_traverser (PangoMatrix trans, SCM expr) {
  [...]
  else if (scm_car (expr) == ly_symbol2scm ("skyline-stencil")) {
      SCM skyline_stencil = scm_cadr (expr);
      return stencil_traverser (trans, skyline_stencil);
  }

Maybe having 'skyline_stencil' as an automatic variable and also a
function parameter, which would be optimized to a different automatic
variable 'expr' in the same function, confuses the reference counting in
Guile's garbage-collection.

The current patches for our tracked issues 3255 and 3522 avoid creating
SCM data types in the C code, and did not show extra memory in the
profile output, so seem be safe enough.

https://codereview.appspot.com/12957047/