[clang] [flang] [clang][flang] Add support for -finit-local-zero (PR #159788)

[via cfe-commits]

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@@ -5877,6 +6030,57 @@ class FirConverter : public Fortran::lower::AbstractConverter {
   void instantiateVar(const Fortran::lower::pft::Variable &var,
                       Fortran::lower::AggregateStoreMap &storeMap) {
     Fortran::lower::instantiateVariable(*this, var, localSymbols, storeMap);
+
+    /// Implicit assignment is defined by the `-finit-*` family of flags.
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jeanPerier wrote:

Can you move the logic to where other cases of initializations is handled  in [`instantiateLocal`](https://github.com/llvm/llvm-project/blob/655de70c485ef165b6e9576a50686aac629e2711/flang/lib/Lower/ConvertVariable.cpp#L1094).
That way, it is a lot clearer that this code is not overriding any initializations.

https://github.com/llvm/llvm-project/pull/159788