[clang] [clang][analyzer] Extend lifetime of dynamic extent information (PR #163562)

[Balázs Kéri via cfe-commits]

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@@ -381,30 +381,12 @@ int *symbolicExtent(int arg) {
     return 0;
   int *mem = (int*)malloc(arg);
 
-  // TODO: without the following reference to 'arg', the analyzer would discard
-  // the range information about (the symbolic value of) 'arg'. This is
-  // incorrect because while the variable itself is inaccessible, it becomes
-  // the symbolic extent of 'mem', so we still want to reason about its
-  // potential values.
-  (void)arg;
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balazske wrote:

I checked the Analysis tests but did not find similar casts (for purpose of keeping constraints of dynamic extent), just one place (that is changed in the last commit).

https://github.com/llvm/llvm-project/pull/163562