FpDebug: Fix SEH-finally block detection on Win

components/fpdebug/fpdbgdwarf.pas

@@ -1111,6 +1111,7 @@ DECL = DW_AT_decl_column, DW_AT_decl_file, DW_AT_decl_line
 
     property DbgInfo: TFpDwarfInfo read FDwarf;
     property ProcAddress: TDBGPtr read FAddress;
+    property AddressInfo: PDwarfAddressInfo read FAddressInfo;
   public
     constructor Create(ACompilationUnit: TDwarfCompilationUnit; AInfo: PDwarfAddressInfo; AAddress: TDbgPtr; ADbgInfo: TFpDwarfInfo = nil); overload;
     destructor Destroy; override;

components/fpdebug/fpdbgdwarffreepascal.pas

@@ -2505,9 +2505,11 @@ function TFpSymbolDwarfFreePascalDataProc.ResolveInternalFinallySymbol(
 {$IfDef WINDOWS}
 var
   StartPC, EndPC: TDBGPtr;
-  HelpSymbol, HelpSymbol2: TFpSymbolDwarf;
+  HelpSymbol2: TFpSymbolDwarf;
   AnAddresses: TDBGPtrArray;
   FndLine, i: Integer;
+  SM1: TDwarfLineInfoStateMachine;
+  ThePrologueLineNum, TheStartLine: Cardinal;
 {$EndIf}
 begin
   Result := Self;
@@ -2517,37 +2519,44 @@ begin
   // On Windows: If in an SEH finally block, try to get the real procedure
   // Look for the line, before the finally statement.
   // TODO: This needs to move to a win-specific class, and ideally a FPC specific class too.
-  if ('$fin' = copy(Name,1, 4) ) and
+debugln(['=========== !!!!!!!! ',Name ]);
+  if ( ('$fin' = copy(Name,1, 4)) or ('fin$' = copy(Name,1, 4)) ) and
      CompilationUnit.GetProcStartEnd(ProcAddress, StartPC, EndPC) and
      (StartPC <> 0)
   then begin
-    // TODO: use the assembler to skip the prologue
-    StartPC := StartPC + 9; // fpc puts the first 9 bytes on "end"
+    (* The first line is the prologue and usually FPC stores the "end" line number.
+       Get the 2nd line number in the finally-proc and see if it is before the prologue *)
+    TheStartLine := 0;
+    SM1 := AddressInfo^.StateMachine.Clone;
+    ThePrologueLineNum := SM1.Line;
+debugln(['=========== !!!!!!!! PL ', ThePrologueLineNum]);
+    SM1.NextLine;
+    if not SM1.EndSequence then begin
+      TheStartLine := SM1.Line;
+debugln(['=========== !!!!!!!! SL ', TheStartLine]);
+      if (TheStartLine=0) or (TheStartLine=ThePrologueLineNum) then begin
+        SM1.NextLine;
+        if not SM1.EndSequence then
+          TheStartLine := SM1.Line;
+debugln(['=========== !!!!!!!! SL ', TheStartLine]);
+      end;
+    end;
+    if (TheStartLine > ThePrologueLineNum) or (TheStartLine = 0) then
+      TheStartLine := ThePrologueLineNum;
+    SM1.Free;
+debugln(['=========== !!!!!!!! SL <<<< ', TheStartLine]);
+
+
     if EndPC < StartPC then
       EndPC := StartPC;
 
-    if StartPC = ProcAddress then begin
-      TFpSymbol(HelpSymbol) := Self;
-      HelpSymbol.AddReference;
-    end
-    else
-      TFpSymbol(HelpSymbol) := DbgInfo.FindProcSymbol(StartPC); // same proc as self, but will return the FIRTS line
-
-    if (HelpSymbol = nil) or (HelpSymbol.CompilationUnit <> CompilationUnit) or
-       (not HelpSymbol.InheritsFrom(TFpSymbolDwarfFreePascalDataProc))
-    then begin
-      HelpSymbol.ReleaseReference;
-      exit
-    end;
-
     AnAddresses := nil;
-    if
-       //(FndLine = HelpSymbol.Line) and
-       HelpSymbol.CompilationUnit.Owner.GetLineAddresses(HelpSymbol.FileName, HelpSymbol.Line, AnAddresses, fsBefore, @FndLine) and
+    if CompilationUnit.Owner.GetLineAddresses(FileName, TheStartLine, AnAddresses, fsBefore, @FndLine) and
        (Length(AnAddresses) > 1)  // may be an internal finally on the begin/end line, sharing a line number
     then begin
+debugln(['=========== !!!!!!!! AAAA ', Length(AnAddresses) ]);
       for i := 0 to Length(AnAddresses) - 1 do
-        if (AnAddresses[i] < StartPC - 9) or (AnAddresses[i] > EndPC) then begin
+        if (AnAddresses[i] < StartPC) or (AnAddresses[i] > EndPC) then begin
           TFpSymbol(HelpSymbol2) := DbgInfo.FindProcSymbol(AnAddresses[i]);
           if (HelpSymbol2 <> nil) and (HelpSymbol2.CompilationUnit = CompilationUnit) and
              (HelpSymbol2.InheritsFrom(TFpSymbolDwarfFreePascalDataProc)) and
@@ -2556,7 +2565,6 @@ begin
             Result := HelpSymbol2;
             // *** FOrigSymbol has now the reference that the caller had. ***
             TFpSymbolDwarfFreePascalDataProc(Result).FOrigSymbol := Self;
-            HelpSymbol.ReleaseReference;
             exit;
           end;
           HelpSymbol2.ReleaseReference;
@@ -2564,8 +2572,10 @@ begin
     end;
 
     AnAddresses := nil;
-    if HelpSymbol.CompilationUnit.Owner.GetLineAddresses(HelpSymbol.FileName, HelpSymbol.Line-1, AnAddresses, fsBefore)
+    if CompilationUnit.Owner.GetLineAddresses(FileName, TheStartLine-1, AnAddresses, fsBefore)
     then begin
+debugln(['=========== !!!!!!!! BBB', Length(AnAddresses) ]);
+
       TFpSymbol(HelpSymbol2) := DbgInfo.FindProcSymbol(AnAddresses[0]);
       if (HelpSymbol2 <> nil) and (HelpSymbol2.CompilationUnit = CompilationUnit) and
          (HelpSymbol2.InheritsFrom(TFpSymbolDwarfFreePascalDataProc))
@@ -2573,12 +2583,10 @@ begin
         Result := HelpSymbol2;
         // *** FOrigSymbol has now the reference that the caller had. ***
         TFpSymbolDwarfFreePascalDataProc(Result).FOrigSymbol := Self;
-        HelpSymbol.ReleaseReference;
         exit;
       end;
       HelpSymbol2.ReleaseReference;
     end;
-    HelpSymbol.ReleaseReference;
   end;
   {$EndIf}
 end;

components/lazdebuggers/lazdebuggerfp/test/testwatches.pas

@@ -518,6 +518,10 @@ begin
     Debugger.SetBreakPoint(Src, 'WatchesScopeUnit2.pas', 'MethodMainBaseBase');
 
     Debugger.SetBreakPoint(Src, 'Prg');
+
+    Debugger.SetBreakPoint(Src, 'FuncFin1');
+    Debugger.SetBreakPoint(Src, 'FuncFin2');
+    Debugger.SetBreakPoint(Src, 'FuncFin3');
     AssertDebuggerNotInErrorState;
 
     (* ************ Nested Functions ************* *)
@@ -604,6 +608,37 @@ begin
     t.EvaluateWatches;
     t.CheckResults;
 
+
+    (* ************ finally ************* *)
+
+    Debugger.RunToNextPause(dcRun);
+    AssertDebuggerState(dsPause);
+    t.Clear;
+    t.Add('FinFoo1', 'FinFoo1' , 123);
+    t.Add('FinFoo2', 'FinFoo2' , 456);
+    t.Add('FinFoo3', 'FinFoo3' , 789);
+    t.EvaluateWatches;
+    t.CheckResults;
+
+    Debugger.RunToNextPause(dcRun);
+    AssertDebuggerState(dsPause);
+    t.Clear;
+    t.Add('FinFoo1', 'FinFoo1' , 123);
+    t.Add('FinFoo2', 'FinFoo2' , 456);
+    t.Add('FinFoo3', 'FinFoo3' , 789);
+    t.EvaluateWatches;
+    t.CheckResults;
+
+    Debugger.RunToNextPause(dcRun);
+    AssertDebuggerState(dsPause);
+    t.Clear;
+    t.Add('FinFoo1', 'FinFoo1' , 123);
+    t.Add('FinFoo2', 'FinFoo2' , 456);
+    t.Add('FinFoo3', 'FinFoo3' , 789);
+    t.EvaluateWatches;
+    t.CheckResults;
+
+
   finally
     Debugger.RunToNextPause(dcStop);
     t.Free;

components/lazdebuggers/lazdebugtestbase/testapps/WatchesScopePrg.pas

@@ -243,7 +243,23 @@ begin
   BreakDummy := 1; // TEST_BREAKPOINT=FuncFoo
 end;
 
-
+procedure TestFin;
+var
+  FinFoo1, FinFoo2, FinFoo3: integer;
+  a: Integer;
+begin
+  try
+    FinFoo1 := 123;
+    FinFoo2 := 456;
+    FinFoo3 := 789;
+  finally
+    a := FinFoo1;           // TEST_BREAKPOINT=FuncFin1
+    a := a + FinFoo2 + 1;
+    a := a + FinFoo3 + 2;   // TEST_BREAKPOINT=FuncFin2
+    a := a + FinFoo1;
+    FinFoo1 := a;           // TEST_BREAKPOINT=FuncFin3
+  end;
+end;
 
 begin
   Unit1Init;
@@ -266,4 +282,6 @@ begin
   TestClassMainChild.MethodMainBaseBase();
 
   BreakDummy := 1; // TEST_BREAKPOINT=Prg
+
+  TestFin;
 end.