Avoid undefined behavior using CFlatData in CScript serialization #4293
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The test is passed. |
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Thanks for testing @LongShao007 |
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ACK |
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Untested ACK. |
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Automatic sanity-testing: PASSED, see http://jenkins.bluematt.me/pull-tester/p4293_2ede43ebe0e87f982747feaec62aeefaf12c3a41/ for binaries and test log. |
`&vch[vch.size()]` and even `&vch[0]` on vectors can cause assertion errors with VC in debug mode. This is the problem mentioned in bitcoin#4239. The deeper problem with this is that we rely on undefined behavior. - Add `begin_ptr` and `end_ptr` functions that get the beginning and end pointer of vector in a reliable way that copes with empty vectors and doesn't reference outside the vector (see https://stackoverflow.com/questions/1339470/how-to-get-the-address-of-the-stdvector-buffer-start-most-elegantly/1339767#1339767). - Add a convenience constructor to CFlatData that wraps a vector. I added `begin_ptr` and `end_ptr` as separate functions as I imagine they will be useful in more places.
laanwj
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Jun 23, 2014
fa126ef Avoid undefined behavior using CFlatData in CScript serialization (Wladimir J. van der Laan)
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&vch[vch.size()]and even&vch[0]on vectors can cause assertion errors with VC in debug mode. This is the problem mentioned in #4239. The deeper problem with this is that we rely on undefined behavior.begin_ptrandend_ptrfunctions that get the beginning and end pointer of vector in a reliable way that copes with empty vectors and doesn't reference outside the vector (see https://stackoverflow.com/questions/1339470/how-to-get-the-address-of-the-stdvector-buffer-start-most-elegantly/1339767#1339767).I added
begin_ptrandend_ptras separate functions as I imagine they will be useful in more places.@LongShao007 this was your issue, can you help test?