Remove unnecessary null pointer checks (ASWF issue #257) #2046
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…dation#257. There only appeared to be one obvious case left. Code search process: grep -C 3 delete . ... then look for if statements, in C-like code, conditioned on the same variable, and no other obvious purpose that required the if statement. Signed-off-by: Eric Powers <[email protected]>
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CLA Not Signed... working this internally... |
| @@ -1968,7 +1968,7 @@ void Grid<BuildT>::operator()(const Func& func, const CoordBBox& bbox, ValueType | |||
| NANOVDB_ASSERT(leaf == nullptr); | |||
| } | |||
| }// loop over sub-part of leafBBox | |||
| if (leaf) delete leaf; | |||
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Ah, the ghost of past compilers continue to haunt us.
Thankfully modern compilers and language specs have unified so we can reliably not test for null before deleting.
| @@ -2985,7 +2985,6 @@ vdbJSON() | |||
| GA_PrimitiveJSON* json = new geo_PrimVDBJSON; | |||
| if (nullptr != theJSON.compare_swap(nullptr, json)) { | |||
| delete json; | |||
| json = nullptr; | |||
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It is correct that this is unnecessary as written.
However, future code COULD be written after the if(); which would then have a stale pointer. So there is a potential benefit.
I do not think there is a harm in execution time; as the compiler should easily reason that this stack variable is unused prior to leaving scope and remove the assignment automatically.
So while I wouldn't advocate necessarily writing this in the first place, I do not think it is something we should remove. (it is even possible some earlier version of the code used json afterwards? So if someone brings back that; we want to keep the assignment?)
In any case, this is under the "reference" section because we do not actively compile this as part of the OpenVDB library, as it is kept as a mirror of the internal Houdini code.
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You're right... that's a good pattern to repeat.
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Force pushed with only the one commit, for review @jmlait
Fix remove unnecessary null pointer checks, issue #257.
There only appeared to be one obvious case left.
Code search process:
... then look for if statements, in C-like code, conditioned on the same variable, and no other obvious purpose that required the if statement.
See:
#257