> -----Ursprüngliche Nachricht----- > Von: skaller <skaller <at> users <dot> sourceforge <dot> net> > Gesendet: 21.03.06 20:31:08
> On Tue, 2006-03-21 at 19:52 +0100, Bernhard Loos wrote: > > Hello > > > > Is there any progress in solving the problem mentioned in this thread: > > http://cygwin.com/ml/cygwin/2006-03/msg00274.html ? > > The example in that page is bugged and there is no > reason at all to expect it to work. > > The mainline ct.c is a C program, it's compiled > as a C program, and so cannot interact with C++ > libraries. If the C++library declares its calls as 'extern "C"' (as it is done in the example), AFAIK there shouldn't be any problem. > The mainline of any body of code using C++ MUST be > compiled as C++. Furthermore you must NOT explicitly > link libstdc++, that is the job of the compiler. Yes, but removing the -lstdc++ doesn't make any difference in this example. > The fact that the example works when libstdc++ is linked > with the mainline simply suggests an implementation artefact > that some startup code is stored in the library and the linker > manages to execute it. It isn't linked against libstdc++. (At least, I don't see, why ist should be.) > There's no assurance this is actually initialising everything > correctly. Some initialisation may need to be done 'on the > bottom of the stack' and/or before other code, and it is too > late when a dll is called half way through the program. > > -- > John Skaller <skaller at users dot sf dot net> > Felix, successor to C++: http://felix.sf.net Anyway all this things aren't really related to the crash. I removed as much things as possible from the testcase and corrected the things mentioned above. But I wasn't able to find a solution or even an explaination. This is a part of the log from depency walker: 00:00:00.438: LoadLibraryA("H:\cygwin\test\CrashTest\CrashTest.dll") called from "CYGWIN1.DLL" at address 0x6100FCB2 by thread 1. 00:00:00.500: Loaded "CRASHTEST.DLL" at address 0x00B40000 by thread 1. Successfully hooked module. 00:00:00.500: DllMain(0x00B40000, DLL_PROCESS_ATTACH, 0x00000000) in "CRASHTEST.DLL" called by thread 1. 00:00:00.500: First chance exception 0xC0000005 (Access Violation) occurred in "CYGWIN1.DLL" at address 0x610AE938 by thread 1. 00:00:00.500: Unloaded "CRASHTEST.DLL" at address 0x00B40000 by thread 1. 00:00:00.516: LoadLibraryA("H:\cygwin\test\CrashTest\CrashTest.dll") returned NULL by thread 1. Error: Unzulssiger Zugriff auf einen Speicherbereich (998). 00:00:00.578: First chance exception 0xC0000005 (Access Violation) occurred at address 0x00B4F37E by thread 1. 00:00:00.578: First chance exception 0xC0000005 (Access Violation) occurred in "CYGWIN1.DLL" at address 0x6108DFFC by thread 1. 00:00:00.578: First chance exception 0xC0000005 (Access Violation) occurred in "CYGWIN1.DLL" at address 0x6108DFFC by thread 1. 00:00:00.578: First chance exception 0xC0000005 (Access Violation) occurred in "CYGWIN1.DLL" at address 0x6108DFFC by thread 1. The DllMain fails for some reason. The program crashs with a stack-overflow after a few hundred lines of like the last three. With 1.5.18, everything works as aspected. file ct.cc: ------------------------------------------------------------------------------- #include <stdio.h> #include <dlfcn.h> extern "C" void test(); int main(int argc, char** argv) { char* pszdll="./CrashTest.dll"; printf("\n\ndlopening %s\n", pszdll); void* hDLL = dlopen(pszdll, 0); if(hDLL) { printf("OK\n"); } else printf("Error dlopening %s\n", pszdll); return 0; } #ifdef HARDLINKTEST void TestLinked(char* pszdll) { test(); } #endif ------------------------------------------------------------------ crashtest.cc: ------------------------------------------------------------------ #include <iostream> extern "C" __declspec(dllexport) void test() { return; } ----------------------------------------------------------------- compile with: g++ -W -Wall -g -DMAKEDLL -DDEBUG CrashTest.cc -shared -o CrashTest.dll g++ -g -W -Wall -DUSEDLL -DDEBUG ct.cc -o ctCRASH.exe g++ -W -Wall -DHARDLINKTEST -DUSEDLL -DDEBUG ct.cc -o ctOK.exe -L./ -lCrashTest Bernhard Loos ______________________________________________________________________ XXL-Speicher, PC-Virenschutz, Spartarife & mehr: Nur im WEB.DE Club! Jetzt gratis testen! http://freemail.web.de/home/landingpad/?mc=021130 -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
