[guitargeek]

The integral of a RooRealSumPdf reuses the translation of the sum itself, which placed its generated code via addToCodeBody(&arg, ...). Since the sum depends on the observables, the integral code ended up inside the event loop, even though the integral itself is data-independent.

For an extended RooRealSumPdf, the same integral is the pdf normalization inside the loop and the expected number of events that the extended term reads after the loop. Because codegen caches results by node name, the post-loop term referenced a loop-local variable and cling refused to compile the generated function:

error: use of undeclared identifier 't14'
    RooNLLVarNewResult += t14 - RooNLLVarNewWeightSum * std::log(t14);

Decide the scope of the generated code from the inputs of the sum instead of from the pdf node: the code is scope-independent if all functions (or component integrals) and coefficients are. For the pdf itself this is equivalent to the previous check, because the sum depends on the data exactly when one of its inputs does. For the integral it keeps the code outside the loop unless a coefficient depends on the data. This needs CodegenContext::isScopeIndependent() to be public.

Add an extended RooRealSumPdf case to testRooFuncWrapper that fails without the fix.

🤖 Done with the help of AI

[github-actions]

Test Results

    24 files      24 suites   4d 3h 5m 29s ⏱️
 3 889 tests  3 884 ✅ 0 💤 5 ❌
83 243 runs  83 238 ✅ 0 💤 5 ❌

For more details on these failures, see this check.

Results for commit 6d079f2.

♻️ This comment has been updated with latest results.