[libc] [llvm] [compiler-rt] [libcxx] [flang] [clang] [Clang] Use correct base expression for counted_by field (#73168) (PR #73465)

[Aaron Ballman via cfe-commits]

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@@ -916,7 +916,7 @@ CodeGenFunction::emitFlexibleArrayMemberSize(const Expr *E, unsigned Type,
 
   // Build a load of the counted_by field.
   bool IsSigned = CountedByFD->getType()->isSignedIntegerType();
-  const Expr *CountedByExpr = BuildCountedByFieldExpr(Base, CountedByFD);
+  Expr *CountedByExpr = BuildCountedByFieldExpr(Base, CountedByFD);
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AaronBallman wrote:

Why did we need to drop the `const` here?

https://github.com/llvm/llvm-project/pull/73465