OpenSystemsDevelopment / qpdf

Authored by Jay Berkenbilt 2010-06-06 12:34:27 +0000


git-svn-id: svn+q:///qpdf/trunk@974 71b93d88-0707-0410-a8cf-f5a4172ac649

Showing 1 changed file with 44 additions and 0 deletions

TODO

	1	+Bug
	2	+===
	3	+
	4	+ * There is a memory leak that happens whenever object A refers to
	5	+ object B which refers back to object A. We have the following
	6	+ pattern:
	7	+
	8	+ #include "PointerHolder.hh"
	9	+
	10	+ class A
	11	+ {
	12	+ public:
	13	+ PointerHolder<A> a;
	14	+ };
	15	+
	16	+ int main()
	17	+ {
	18	+ A a1;
	19	+ a1.a = new A();
	20	+ a1.a.getPointer()->a = new A();
	21	+ a1.a.getPointer()->a.getPointer()->a = a1.a;
	22	+ return 0;
	23	+ }
	24	+
	25	+ In order to fix this, we have to explicitly break circular
	26	+ references, but we have to do this at a time that doesn't
	27	+ completely destroy performance.
	28	+
	29	+ To debug, configure with
	30	+
	31	+ ./configure --disable-shared --disable-test-compare-images \
	32	+ CFLAGS=-g CXXFLAGS=-g
	33	+
	34	+ Current code causes test failures. linearize segfaults on
	35	+ hybrid-xref.pdf, and the test suite fails in various places. Maybe
	36	+ because we don't do any kind of loop detection?
	37	+
	38	+ Use valgrind --leak-check=full to see leak details.
	39	+
	40	+ The file memory-leak.pdf is a minimal case that shows the problem.
	41	+
	42	+ Files in trace having tracing to show which objects haven't been
	43	+ allocated.
	44	+
1	45	Next
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