Disable GC on logp_dlogp function

Related to #7539

pymc/model/core.py

@@ -32,7 +32,7 @@
 import pytensor.tensor as pt
 import scipy.sparse as sps
 
-from pytensor.compile import DeepCopyOp, Function, get_mode
+from pytensor.compile import DeepCopyOp, Function, Mode, get_mode
 from pytensor.compile.sharedvalue import SharedVariable
 from pytensor.graph.basic import Constant, Variable, graph_inputs
 from pytensor.tensor.random.op import RandomVariable
@@ -253,6 +253,14 @@ def __init__(
                 )
             inputs = grad_vars
 
+        # If default C-backend mode, create function without gc
+        if (
+            "mode" not in kwargs
+            and pytensor.config.mode == "Mode"
+            and pytensor.config.linker == "cvm"
+            and pytensor.config.optimizer == "o4"
+        ):
+            kwargs["mode"] = Mode(linker="cvm_nogc", optimizer="o4")
         self._pytensor_function = compile_pymc(inputs, outputs, givens=givens, **kwargs)
         self._raveled_inputs = ravel_inputs