The regression tests sort/sort_0{1,2,3,4}.szl all fail in -N (native) mode on
x86_64 Ubuntu 13.04 when compiled with -O1 or higher. Compiling
nativecodegen.cc with -O0 is a workaround.
The root cause appears to be that FunctionCall (a class defined in
nativecodegen.cc) copies a reference-typed constructor argument to a
reference-typed member variable, and then accesses it in ~FunctionCall after
the original constructor argument has been deallocated by the caller. To put it
another way, each FunctionCall retains a pointer to a stack object and
dereferences it after its lifetime has expired. The decision to use '&' instead
of '*' rendered the bug difficult to see on code review.
One-byte code patch attached, representing two days of debugging work. Two
days. One byte. This is why I hate C++.
Original issue reported on code.google.com by aecolley on 20 Oct 2013 at 4:05
Original issue reported on code.google.com by
aecolleyon 20 Oct 2013 at 4:05Attachments: