Attribute cleanup actions at the end of a function body to its closing brace [GH edgcpp#309]

Author: daveedvdv-nvidia

src/Changes

@@ -1,5 +1,22 @@
 Version 7.1
 
+10/15/26  [GH #309]
+Position of (lowered) cleanups at the end of a function body
+
+The cleanup actions (e.g., destructor calls) performed when control reaches
+the end of a function body were attributed to the source position of the
+preceding statement instead of to that of the closing brace of the function
+body.  That is now fixed.  For example:
+
+  int v = 0;
+  struct D { ~D() { v = v + 1; } };
+  void f() {
+    D d;
+    v = 2;
+  }  // The call of d's destructor is now positioned on this line.
+     // Previously it was positioned on the line with "v = 2;" above.
+
+
 10/16/26 [GH #302]
 Incorrect order of base-class initializers in class template
 

src/lower_il.c

@@ -19288,12 +19288,27 @@ Lower an stmk_return statement.
   }  /* if */
   if (any_cleanup_on_return) {
     /* Generate any cleanup actions required on exit from the routine. */
-    if (make_block) {
-      /* Turn the return into a block so that code can be inserted
-         in front of the return. */
-      turn_branch_into_block(statement, &insert_location, &return_statement);
-    }  /* if */
-    gen_cleanup_actions(innermost_function_scope->lifetime, &insert_location);
+    { Value_saver<a_source_position> saved_code_pos(&code_pos_for_lowering);
+      Value_saver<a_source_position> saved_error_position(&error_position);
+
+      if (statement->compiler_generated && statement->position.seq == 0) {
+        a_statement_ptr assoc_block = innermost_function_scope->assoc_block;
+        if (assoc_block != NULL &&
+            assoc_block->kind == stmk_block &&
+            assoc_block->variant.block.extra_info->final_position.seq != 0) {
+          code_pos_for_lowering = assoc_block->variant.block.extra_info
+                                                             ->final_position;
+          error_position = code_pos_for_lowering;
+        }  /* if */
+      }  /* if */
+      if (make_block) {
+        /* Turn the return into a block so that code can be inserted
+           in front of the return. */
+        turn_branch_into_block(statement, &insert_location, &return_statement);
+      }  /* if */
+      gen_cleanup_actions(innermost_function_scope->lifetime,
+                          &insert_location);
+    }
     reset_cleanup_state_at_transfer_of_control(return_statement, statement);
   }  /* if */
   /* Maintain a list of all returns in the routine so that epilogue code

tests/expectations/edg_x86_32_cp/regressions.log

@@ -1,3 +1,5 @@
+gh-309.sft.cpp:fp:-DTEST_NUMBER=1 --g++:REQUIREMENTS NOT MET:
+gh-309.sft.cpp:fp:-DTEST_NUMBER=2 --g++ --no_exceptions:REQUIREMENTS NOT MET:
 immediate-pragma-lost.sft.cpp:cppbe:-DTEST_NUMBER=1:PASS:
 pragma-il-class-no-lowering.sft.cpp:fp:-DTEST_NUMBER=1:REQUIREMENTS NOT MET:
 pragma-il-class.sft.cpp:fp:-DTEST_NUMBER=1:REQUIREMENTS NOT MET:

tests/expectations/edg_x86_64_cp/regressions.log

@@ -1,3 +1,5 @@
+gh-309.sft.cpp:fp:-DTEST_NUMBER=1 --g++:REQUIREMENTS NOT MET:
+gh-309.sft.cpp:fp:-DTEST_NUMBER=2 --g++ --no_exceptions:REQUIREMENTS NOT MET:
 immediate-pragma-lost.sft.cpp:cppbe:-DTEST_NUMBER=1:PASS:
 pragma-il-class-no-lowering.sft.cpp:fp:-DTEST_NUMBER=1:REQUIREMENTS NOT MET:
 pragma-il-class.sft.cpp:fp:-DTEST_NUMBER=1:REQUIREMENTS NOT MET:

tests/tests/regressions/.gh-309.rto/default.1.1.txt

@@ -0,0 +1,4 @@
+fe_only -DTEST_NUMBER=1 --g++ Test_name.c
+destructor call on line 14
+destructor call on line 18
+destructor call on line 20

tests/tests/regressions/.gh-309.rto/default.2.1.txt

@@ -0,0 +1,4 @@
+fe_only -DTEST_NUMBER=2 --g++ --no_exceptions Test_name.c
+destructor call on line 14
+destructor call on line 18
+destructor call on line 20

tests/tests/regressions/gh-309.sft.cpp

@@ -0,0 +1,20 @@
+//type:fp
+//options:--g++:--g++ --no_exceptions
+//require:BACK_END_IS_C_GEN_BE 1
+//filter:awk '/^#(line)? [0-9]+/ { line = $2; next } /_ZN1DD1Ev\(\(/ { print "destructor call on line " line } { line++ }' Test_name.int.c
+int sink;
+
+struct D {
+  ~D();
+};
+
+void f() {
+  D d;
+  sink = 1;
+}  // The destructor call was previously attributed to the line above.
+
+void g(bool b) {
+  D d;
+  if (b) return;
+  sink = 2;
+}  // The destructor call was previously attributed to the line above.