Debugger: Fix hitting breakpoints repeatedly in multithreading

This change resolves an issue where gdb.parse_and_eval could
rerun the  multithreading application, causing breakpoints to be hit
repeatedly in different threads, leading to an infinite loop.

Added checkbox which enables skipping the execution of
gdb.parse_and_eval in few places that mitigate the issue.

Fixes: QTCREATORBUG-23219
Change-Id: I856d382d033f8a4da394d7422ebb3e131de28e09
Reviewed-by: hjk <hjk@qt.io>

share/qtcreator/debugger/dumper.py

@@ -227,6 +227,7 @@ class DumperBase():
         self.watchers = args.get('watchers', {})
         self.useDynamicType = int(args.get('dyntype', '0'))
         self.useFancy = int(args.get('fancy', '0'))
+        self.allowInferiorCalls = int(args.get('allowinferiorcalls', '0'))
         self.forceQtNamespace = int(args.get('forcens', '0'))
         self.passExceptions = int(args.get('passexceptions', '0'))
         self.isTesting = int(args.get('testing', '0'))

share/qtcreator/debugger/gdbbridge.py

@@ -739,6 +739,9 @@ class Dumper(DumperBase):
     def nativeParseAndEvaluate(self, exp):
         #self.warn('EVALUATE "%s"' % exp)
         try:
+            if not self.allowInferiorCalls:
+                return None
+
             val = gdb.parse_and_eval(exp)
             return val
         except RuntimeError as error:
@@ -772,6 +775,9 @@ class Dumper(DumperBase):
         #self.warn('PTR: %s -> %s(%s)' % (value, function, addr))
         exp = '((%s*)0x%x)->%s(%s)' % (type_name, addr, function, arg)
         #self.warn('CALL: %s' % exp)
+        if not self.allowInferiorCalls:
+            return None
+
         result = gdb.parse_and_eval(exp)
         #self.warn('  -> %s' % result)
         res = self.fromNativeValue(result)
@@ -1504,6 +1510,12 @@ class CliDumper(Dumper):
 
         args = {}
         args['fancy'] = 1
+        # It enables skipping the execution of gdb.parse_and_eval which prevents the application from being rerun,
+        # which could lead to hitting breakpoints repeatedly in different threads, causing an infinite loop.
+        # Currently, gdb.parse_and_eval is bypassed in several places, resolving the bug QTCREATORBUG-23219.
+        # In the future, a full wrapper for gdb.parse_and_eval might be necessary to avoid this issue entirely.
+        # For now, we leave it as-is to retain as much pretty-printing functionality as possible.
+        args['allowinferiorcalls'] = 1
         args['passexceptions'] = 1
         args['autoderef'] = 1
         args['qobjectnames'] = 1

src/plugins/debugger/commonoptionspage.cpp

@@ -235,6 +235,10 @@ LocalsAndExpressionsSettings::LocalsAndExpressionsSettings()
     useDebuggingHelpers.setDefaultValue(true);
     useDebuggingHelpers.setLabelText(Tr::tr("Use Debugging Helpers"));
 
+    allowInferiorCalls.setSettingsKey(debugModeGroup, "AllowInferiorCalls");
+    allowInferiorCalls.setDefaultValue(true);
+    allowInferiorCalls.setLabelText(Tr::tr("Allow inferior calls in debugging helper"));
+
     useCodeModel.setSettingsKey(debugModeGroup, "UseCodeModel");
     useCodeModel.setDefaultValue(true);
     useCodeModel.setLabelText(Tr::tr("Use code model"));
@@ -354,6 +358,7 @@ LocalsAndExpressionsSettings::LocalsAndExpressionsSettings()
 
         return Column {
             useDebuggingHelpers,
+            allowInferiorCalls,
             useHelper,
             Space(10),
             showStdNamespace,

src/plugins/debugger/commonoptionspage.h

@@ -76,6 +76,7 @@ public:
     LocalsAndExpressionsSettings();
 
     Utils::BoolAspect useDebuggingHelpers{this};
+    Utils::BoolAspect allowInferiorCalls{this};
     Utils::BoolAspect useCodeModel{this};
     Utils::BoolAspect showThreadNames{this};
     Utils::FilePathAspect extraDumperFile{this};   // For loading a file. Recommended.

src/plugins/debugger/debuggeractions.cpp

@@ -76,6 +76,7 @@ DebuggerSettings::DebuggerSettings() :
 
     // Page 4
     useDebuggingHelpers{localsAndExpressionSettings().useDebuggingHelpers},
+    allowInferiorCalls{localsAndExpressionSettings().allowInferiorCalls},
     useCodeModel{localsAndExpressionSettings().useCodeModel},
     showThreadNames{localsAndExpressionSettings().showThreadNames},
     extraDumperFile{localsAndExpressionSettings().extraDumperFile},   // For loading a file. Recommended.

src/plugins/debugger/debuggeractions.h

@@ -65,6 +65,7 @@ public:
 
     // Page 4: Locals and expressions
     Utils::BoolAspect &useDebuggingHelpers;
+    Utils::BoolAspect &allowInferiorCalls;
     Utils::BoolAspect &useCodeModel;
     Utils::BoolAspect &showThreadNames;
     Utils::FilePathAspect &extraDumperFile;   // For loading a file. Recommended.

src/plugins/debugger/gdb/gdbengine.cpp

@@ -145,6 +145,8 @@ GdbEngine::GdbEngine()
             this, &GdbEngine::createFullBacktrace);
     connect(&s.useDebuggingHelpers, &BaseAspect::changed,
             this, &GdbEngine::reloadLocals);
+    connect(&s.allowInferiorCalls, &BaseAspect::changed,
+            this, &GdbEngine::reloadLocals);
     connect(&s.useDynamicType, &BaseAspect::changed,
             this, &GdbEngine::reloadLocals);
 
@@ -2638,6 +2640,7 @@ void GdbEngine::insertBreakpoint(const Breakpoint &bp)
                 const DebuggerSettings &s = settings();
                 cmd.arg("passexceptions", alwaysVerbose);
                 cmd.arg("fancy", s.useDebuggingHelpers());
+                cmd.arg("allowinferiorcalls", s.allowInferiorCalls());
                 cmd.arg("autoderef", s.autoDerefPointers());
                 cmd.arg("dyntype", s.useDynamicType());
                 cmd.arg("qobjectnames", s.showQObjectNames());
@@ -5164,6 +5167,7 @@ void GdbEngine::doUpdateLocals(const UpdateParameters &params)
     const DebuggerSettings &s = settings();
     cmd.arg("passexceptions", alwaysVerbose);
     cmd.arg("fancy", s.useDebuggingHelpers());
+    cmd.arg("allowinferiorcalls", s.allowInferiorCalls());
     cmd.arg("autoderef", s.autoDerefPointers());
     cmd.arg("dyntype", s.useDynamicType());
     cmd.arg("qobjectnames", s.showQObjectNames());