[llvm] [Kaleidoscope] Fix ForExprAST::codegen (PR #88207)

[via llvm-commits]

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@@ -13,4 +13,4 @@ def fibi(x)
   b;
 
 fibi(10);
-# CHECK: Evaluated to 55.000000
+# CHECK: Evaluated to 34.000000
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Logikable wrote:

Could we leave this as 55 and change the check to `i < x + 1`? In Chapter 7, there are recursive and iterative implementations of fib(). With the current changes, these implementations will diverge.

This would also require changes to LangImpl07.rst.

https://github.com/llvm/llvm-project/pull/88207