There are, sadly, many combinations of linkage in use throughout the tree.
The main differentiator, though, is between program/libraries related to
Gecko or not. Kind of. Some need mozglue, some don't. Some need dependent
linkage, some standalone.
Anyways, these new templates remove the need to manually define the
right dependencies against xpcomglue, nspr, mozalloc and mozglue
in most cases.
Places that build programs and were resetting MOZ_GLUE_PROGRAM_LDFLAGS
or that build libraries and were resetting MOZ_GLUE_LDFLAGS can now
just not use those Gecko-specific templates.
OS_LIBS for libraries that are not part of the gecko tree, EXTRA_LIBS for
libraries, such as NSPR, that are in the tree, but are not handled by
moz.build just yet. Those EXTRA_LIBS may also come from a system library.
However, in cases where the expanded variables are always empty for the
in-tree case, OS_LIBS is used (as for, e.g. MOZ_ZLIB_LIBS). OS_LDFLAGS is
used exclusively for non-library linker flags.
Always pass EXTRA_LIBS before OS_LIBS on linker command lines.
Forbid EXTRA_DSO_LDOPTS, SHARED_LIBRARY_LIBS and LIBS in Makefiles.
There are three categories of improvements:
(1) using size_t* rather than unsigned long* (and "%zX" rather than
"%lX"), to better support platforms where sizeof(long) !=
sizeof(void*), such as Win64 (untested, though). This is a
non-issue for 64-bit Linux (where I tested) and Mac.
(2) Using the correct amount of 0-padding when printing addresses to
show how much memory space is being printed. In other words, using
"%016zX" on 64-bit platforms instead of "%08zX". This change is
cosmetic-only, though it makes the logs much more understandable.
(3) [in leaksoup.cpp only] Fixing an occurrence of assuming that
sizeof(int) == sizeof(void*). This occurrence led to printing only
the lower half of each word in the output, after doing a correct
analysis of the memory graph.
This patch is patching three files:
(A) nsTraceMalloc.cpp, which is the in-process Gecko trace-malloc code
that generates the memory dumps.
(B) adreader.cpp, which is shared utility code for reading such a
memory dump (currently used only by leaksoup.cpp)
(C) leaksoup.cpp, which reads in such a memory dump, performs a
strongly connected components analysis of the memory graph, and
writes it back out, HTML-ized, with the roots listed at the top.
A fourth file appears to need no modification since it only looks at the
stack part of the dump and not the contents of the memory:
(D) diffbloatdump.pl, which diffs two bloat dumps and produces a stack
tree showing the change in allocations between them