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Attached test script, tracetest.py, prints disassembly followed by a trace of the following function:
1 def f():
2 return [i
3 for i
4 in range(2)]
With default configuration, the output is
 2 0 LOAD_CONST 1 (<code object <listcomp> at 0x100484e00, file "tracetest.py", line 2>) 
 3 MAKE_FUNCTION 0 
 4 6 LOAD_GLOBAL 0 (range) 
 9 LOAD_CONST 2 (2) 
 12 CALL_FUNCTION 1 
 15 GET_ITER 
 16 CALL_FUNCTION 1 
 19 RETURN_VALUE 
listcomp:
 2 0 BUILD_LIST 0 
 3 LOAD_FAST 0 (.0) 
 >> 6 FOR_ITER 12 (to 21) 
 3 9 STORE_FAST 1 (i) 
 12 LOAD_FAST 1 (i) 
 15 LIST_APPEND 2 
 18 JUMP_ABSOLUTE 6 
 >> 21 RETURN_VALUE 
['2 0 LOAD_CONST', '4 6 LOAD_GLOBAL', '2 0 BUILD_LIST', '3 9 STORE_FAST', '2 6 FOR_ITER', '3 9 STORE_FAST', '2 6 FOR_ITER']
but with configuration using --without-computed-gotos option, the disassembly is the same, but the trace is different:
['2 0 LOAD_CONST', '4 6 LOAD_GLOBAL', '2 0 BUILD_LIST', '2 6 FOR_ITER', '2 6 FOR_ITER']
This behavior changed between 3.1 and 3.2 (likely in r74132), but it is inconsistent in both versions. Since r74132 changes were not backported to 3.1, I am classifying this as 3.2 only even though the problem is present in 3.1 as well.
See also issues #6042 and #9315.