[lldb-dev] [PATCH] For SBDebugger::Create assertion failure

[Matthew Gardiner]

Hi folks,

Whilst starting to play with the lldb C++ API, I've noticed that this
simple little program causes an assertion failure (and hence a core
dump).

#include <cstdio>
#include "lldb/API/LLDB.h"

int main()
{
    fprintf(stderr, "lldb-app\n");
//  lldb::SBDebugger::Initialize();
    lldb::SBDebugger dbgr = lldb::SBDebugger::Create(true);
    fprintf(stderr, "SBDebugger::Create!\n");
    return 0;
}

As guessed, by uncommenting out the Initialize call, the assertion is
satisfied by Create and friends, and the code runs to completion.

To me, this is bad on 2 counts:

1. If Create depends on Initialize then Initialize should be called
internally.
2. From a public API perspective, even if Create and Initialize need to
be called separately, a crash (failed assert) seems a little harsh.
Shouldn't an error return (or exception throw) be used to communicate
the user's mistake in this case?

I did some digging into SBDebugger::Initialize and it seems safe for
this to be called internally by Create.

So I'm proposing that I fix this issue with following patch:

Index: source/API/SBDebugger.cpp
===================================================================
--- source/API/SBDebugger.cpp	(revision 218974)
+++ source/API/SBDebugger.cpp	(working copy)
@@ -159,6 +159,8 @@
 {
     Log *log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_API));
 
+    Initialize();
+
     SBDebugger debugger;
     
     // Currently we have issues if this function is called
simultaneously on two different
@@ -210,6 +212,8 @@
                      sstr.GetData());
     }
 
+    Terminate();
+
     Debugger::Destroy (debugger.m_opaque_sp);
 
     if (debugger.m_opaque_sp.get() != NULL)


Please shout out if you don't want me to.

thanks
Matt




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