Structs in our style system use an arena-style allocation system,
managed by the presshell to which they belong. All of the relevant
overloads that forward allocation requests to the presshell declare
themselves as CPP_THROW_NEW, which indicates that they do not throw
exceptions. The C++ specification states that operator new overloads
that declare themselves to not throw exceptions require a null check on
their return value. However, the relevant presshell allocation method,
AllocateByObjectID, is infallible and will never return a null pointer.
The callers of all of these methods are therefore doing useless
(compiler-generated) null checks. Let's get rid of those useless checks
by removing the CPP_THROW_NEW annotations. This change declares these
methods will return non-null pointers and throw exceptions in case of
errors--but as we don't use exceptions, and AllocateByObjectID will
abort on OOM, everything works out OK.
Structs in our style system use an arena-style allocation system,
managed by the presshell to which they belong. All of the relevant
overloads that forward allocation requests to the presshell declare
themselves as CPP_THROW_NEW, which indicates that they do not throw
exceptions. The C++ specification states that operator new overloads
that declare themselves to not throw exceptions require a null check on
their return value. However, the relevant presshell allocation method,
AllocateByObjectID, is infallible and will never return a null pointer.
The callers of all of these methods are therefore doing useless
(compiler-generated) null checks. Let's get rid of those useless checks
by removing the CPP_THROW_NEW annotations. This change declares these
methods will return non-null pointers and throw exceptions in case of
errors--but as we don't use exceptions, and AllocateByObjectID will
abort on OOM, everything works out OK.
The bulk of this commit was generated by running:
run-clang-tidy.py \
-checks='-*,llvm-namespace-comment' \
-header-filter=^/.../mozilla-central/.* \
-fix
AllocateByObjectID() is infallible. Therefore the |operator new| of nsFrameList,
nsLineBox and nsRuleNode are too, as is nsRuleNode::CreateRootNode().
The patch also removes a couple of comments duplicated in both .h and .cpp
files.
This patch does the following:
* Move nsIFrame::IntrinsicSize to mozilla::IntrinsicSize so that it can
be forward-declared.
* Move a number of templated inline nsLayoutUtils methods to nsIFrame.
* Use mozilla::layout::FrameChildListID instead of the
nsIFrame::ChildListID typedef in nsLayoutUtils.h.
* Move nsReflowFrameRunnable to its only user, nsProgressMeterFrame.cpp.
* Make a number of functions requiring nsIFrame.h out-of-line.
* Remove the nsIFrame.h #include from nsLayoutUtils.h and add it to the
places which require it implicitly.
"new nsFrameList()" becomes "new (shell) nsFrameList()".
"delete list" becomes "if (list) list->Delete(shell)" - note also that
an additional assertion was added that list is empty when deleted.
"nsAutoPtr<nsFrameList> list(StealSomeFrames())" becomes
"AutoFrameListPtr list(aPresContext, StealSomeFrames())"
Add types to represent identifiers for frame child lists, sets of those
identifiers, and iterators over the child lists of a frame.
Define a enumeration type FrameChildListID representing all of the types
of child lists that frames have (each with a unique bit), a class
FrameChildListIDs for representing any set of FrameChildListID, and a
class FrameChildListIterator for iterating over all of the child lists
of a frame.
