pnnx write implicit int conversion in python script (#5767)

.ci/pnnx.yml

@@ -200,8 +200,8 @@ jobs:
         export OMP_NUM_THREADS=1
         export MKL_NUM_THREADS=1
         export MKL_ENABLE_INSTRUCTIONS=SSE4_2
-        cd tools/pnnx
-        cd build && ctest --output-on-failure -j 16
+        cd tools/pnnx/build
+        ctest --output-on-failure -j 16
 
     - name: python-pnnx
       run: |

tools/pnnx/src/ir.cpp

@@ -1051,7 +1051,7 @@ static std::string expand_expression(const Operator* op)
                  || t == "torch.long")
         {
             std::string unaryop = t;
-            if (t == "int") unaryop = "int";
+            if (t == "int") unaryop = ""; // but the explicit int() causes troubles in tracing
             if (t == "abs") unaryop = "torch.abs";
             if (t == "acos") unaryop = "torch.acos";
             if (t == "acosh") unaryop = "torch.acosh";