[cfe-dev] Diagnostics in plugins fail with assert

[Florian Weimer]

Passing -an-error to the example plugin
(trunk/examples/PrintFunctionNames/PrintFunctionNames.cpp) results in a 
failed assert at include/clang/Basic/Diagnostic.h:1037:

1035	inline DiagnosticBuilder DiagnosticsEngine::Report(SourceLocation Loc,
1036	                                            unsigned DiagID){
1037	  assert(CurDiagID == ~0U && "Multiple diagnostics in flight at 
once!");
1038	  CurDiagLoc = Loc;
1039	  CurDiagID = DiagID;
1040	  return DiagnosticBuilder(this);
1041	}


#4  0x00007ffff7d70cc9 in Report (DiagID=4620, Loc=..., this=0x4481100)
     at /opt/llvm-3.2/include/clang/Basic/Diagnostic.h:1037
#5  Report (DiagID=4620, this=0x4481100) at 
/opt/llvm-3.2/include/clang/Basic/Diagnostic.h:1043
#6  (anonymous namespace)::PrintFunctionNamesAction::ParseArgs 
(this=<optimized out>, CI=..., args=...)
     at plugin.cpp:53
#7  0x0000000000bf2487 in 
clang::FrontendAction::CreateWrappedASTConsumer (this=0x447fec0, CI=..., 
InFile=...)
     at 
/home/fweimer/src/ext/llvm/trunk/tools/clang/lib/Frontend/FrontendAction.cpp:149
#8  0x0000000000bf2bd5 in clang::FrontendAction::BeginSourceFile 
(this=0x447fec0, CI=..., Input=...)
     at 
/home/fweimer/src/ext/llvm/trunk/tools/clang/lib/Frontend/FrontendAction.cpp:245
#9  0x0000000000bca4f3 in clang::CompilerInstance::ExecuteAction 
(this=0x447cd30, Act=...)
     at 
/home/fweimer/src/ext/llvm/trunk/tools/clang/lib/Frontend/CompilerInstance.cpp:671
#10 0x0000000000b9b648 in clang::ExecuteCompilerInvocation (Clang=0x447cd30)
     at 
/home/fweimer/src/ext/llvm/trunk/tools/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:189
#11 0x0000000000b893e2 in cc1_main (ArgBegin=0x7fffffffd058, 
ArgEnd=0x7fffffffd208,
     Argv0=0x447b668 "/opt/llvm-3.2/bin/clang", MainAddr=0xb94ec8)
     at 
/home/fweimer/src/ext/llvm/trunk/tools/clang/tools/driver/cc1_main.cpp:165
#12 0x0000000000b96707 in main (argc_=56, argv_=0x7fffffffdc68)
     at 
/home/fweimer/src/ext/llvm/trunk/tools/clang/tools/driver/driver.cpp:358

This seems to affect all error reporting from plugins.  Is some 
initialization step missing from the example plugin?

This happens with clang trunk (r163897) compiled on Fedora 17 (x86_64), 
in Release and Debug+Asserts builds.

Apart from the missing ability for error reporting, plug-ins seem to run 
just fine.

-- 
Florian Weimer / Red Hat Product Security Team