I'm creating a dynamic upload heap, and uploading some data to it, and have zero issues or warnings. But as soon as I try to read index zero from the HLSL structured buffer (float4 some_data = MyBuffer[0];), I get a _com_error exception when I use SwapChain->Present(). If I remove the shader buffer access line, everything works as expected with no messages.
I'm assuming I'm making a mistake somewhere, and my upload heap is not reaching its target for whatever reason, which means my shader buffer is uninitialized. But this is just a random guess.
Here is the exception message:
Exception thrown at 0x00007FF8A925CD29 in Kestarda.exe: Microsoft C++ exception: _com_error at memory location 0x000000B714CFC7D0.
The exception is being thrown pretty deep in the call stack:
D3D12Core.dll!CDevice::CreateLayeredChild(unsigned int,void const *,unsigned __int64,struct ID3D12LayeredUseCounted *,struct _GUID const &,void * *) Unknown
D3D12Core.dll!CBridgeImpl<struct ID3D12LayeredDevice,struct ID3D12LayeredDevice,class CLayeredObject<class NDXGI::CDevice> >::CreateLayeredChild(unsigned int,void const *,unsigned __int64,struct ID3D12LayeredUseCounted *,struct _GUID const &,void * *) Unknown
d3d12SDKLayers.dll!NDebug::CDeviceChild<struct ID3D12CommandAllocator>::FinalConstruct(enum ED3D12DeviceChildType,struct SLayeredArgs const *,unsigned __int64,unsigned __int64,struct ID3D12LayeredUseCounted *,struct _GUID const &) Unknown
d3d12SDKLayers.dll!CLayeredObject<class NDebug::CCommandAllocator>::CreateInstance(struct NDebug::CCommandAllocator::TConstructorArgs const &,void *,void *,struct _GUID const &,void * *) Unknown
d3d12SDKLayers.dll!NDebug::CDevice::CreateLayeredChild(unsigned int,void const *,unsigned __int64,struct ID3D12LayeredUseCounted *,struct _GUID const &,void * *) Unknown
D3D12.dll!NOutermost::CDevice::CreateLayeredChild(unsigned int,void const *,unsigned __int64,struct ID3D12LayeredUseCounted *,struct _GUID const &,void * *) Unknown
D3D12Core.dll!CDevice::CreateCommandAllocator(enum D3D12_COMMAND_LIST_TYPE,struct _GUID const &,void * *) Unknown
d3d12SDKLayers.dll!NDebug::CDevice::CreateCommandAllocator(enum D3D12_COMMAND_LIST_TYPE,struct _GUID const &,void * *) Unknown
dxgi.dll!CD3D12Device::InitCommandList(unsigned int,enum CD3D12Device::QueueType) Unknown
dxgi.dll!CD3D12Device::CloseAndSubmitCommandList(unsigned int,enum CD3D12Device::QueueType) Unknown
dxgi.dll!CD3D12Device::PresentExtended(struct DXGI_PRESENTSURFACE const *,unsigned int,struct IDXGIResource *,void *,unsigned int,unsigned int,unsigned int,unsigned int *) Unknown
dxgi.dll!CFlipPresentToDWM<CDXGISwapChainWrapper>::FlipPresentCore() Unknown
dxgi.dll!CDXGISwapChain::FlipPresentToDWM() Unknown
dxgi.dll!CDXGISwapChain::PresentImplCore(struct SPresentArgsCore<struct CDXGISwapChainWrapper> const *,unsigned int,struct tagRECT const *,unsigned int,struct DXGI_SCROLL_RECT const *,struct IDXGIResource *,struct CDXGISwapChain::PresentResultActions &) Unknown
dxgi.dll!CDXGISwapChain::PresentImpl() Unknown
dxgi.dll!CDXGISwapChain::Present() Unknown
>> Kestarda.exe!Diligent::SwapChainD3D12Impl::Present(unsigned int SyncInterval) Line 157 C++
Kestarda.exe!KGraphics::SceneShow(bool reset_on_fail) Line 646 C++
Kestarda.exe!KShell::FrameGraphicsEnd() Line 335 C++
Kestarda.exe!KShell::FrameGraphics() Line 362 C++
Kestarda.exe!KShell::FrameExecute() Line 136 C++
Kestarda.exe!MainFrame::LifeCycle::Execute() Line 627 C++
Kestarda.exe!WinMain(HINSTANCE__ * h_instance, HINSTANCE__ * __formal, char * command_line, int __formal) Line 107 C++
I've tried wrapping Present() with a _com_error catch, but it does nothing, both running in the debugger and out of it, I get no messages:
try
{
// attempt to present the scene
System.SwapChain->Present( ... );
}
catch(const _com_error &x)
{
app_error( x.ErrorMessage() );
}
After the _com_error exception, if I continue on, I get a ton of other exceptions about accessing memory location 0x0, then it just shuts down.
Is there any way to debug an issue like this? D3D12 is clearly throwing an exception, but I can't seem to get any information about why?
Related
I am struggling to understand why some of my code using boost, which was working fine under Visual Studio 2017, is now resulting in an access violation under Visual Studio 2019. However, I only encounter this failure under Debug build. Release build works fine, with no issues.
What could I have set up incorrectly in my build, environment, or code, that could cause such a failure?
My environment:
Windows 10
Boost 1.74 (dynamic link)
Visual Studio 2019 v16.7.6
Compiling for C++ x64
The failing line of my code is this:
boost::filesystem::path dir = (boost::filesystem::temp_directory_path() / boost::filesystem::unique_path("%%%%-%%%%-%%%%-%%%%"));
The failing line in Boost filesystem is this here in boost/filesystem/path.hpp:
namespace path_traits
{ // without codecvt
inline
void convert(const char* from,
const char* from_end, // 0 for null terminated MBCS
std::wstring & to)
{
convert(from, from_end, to, path::codecvt());
}
The failure message reported by Visual Studio is as follows:
Exception thrown at 0x00007FF9164F1399 (vcruntime140d.dll) in ezv8.tests.exe: 0xC0000005: Access violation reading location 0xFFFFFFFFFFFFFFFF.
The call stack looks like this:
vcruntime140d.dll!00007ff9164f1550() Unknown
> boost_filesystem-vc142-mt-gd-x64-1_74.dll!wmemmove(wchar_t * _S1, const wchar_t * _S2, unsigned __int64 _N) Line 248 C++
boost_filesystem-vc142-mt-gd-x64-1_74.dll!std::_WChar_traits<wchar_t>::move(wchar_t * const _First1, const wchar_t * const _First2, const unsigned __int64 _Count) Line 204 C++
boost_filesystem-vc142-mt-gd-x64-1_74.dll!std::wstring::append(const wchar_t * const _Ptr, const unsigned __int64 _Count) Line 2864 C++
boost_filesystem-vc142-mt-gd-x64-1_74.dll!std::wstring::append<wchar_t *,0>(wchar_t * const _First, wchar_t * const _Last) Line 2916 C++
boost_filesystem-vc142-mt-gd-x64-1_74.dll!`anonymous namespace'::convert_aux(const char * from, const char * from_end, wchar_t * to, wchar_t * to_end, std::wstring & target, const std::codecvt<wchar_t,char,_Mbstatet> & cvt) Line 77 C++
boost_filesystem-vc142-mt-gd-x64-1_74.dll!boost::filesystem::path_traits::convert(const char * from, const char * from_end, std::wstring & to, const std::codecvt<wchar_t,char,_Mbstatet> & cvt) Line 153 C++
appsvcs.dll!boost::filesystem::path_traits::convert(const char * from, const char * from_end, std::wstring & to) Line 1006 C++
appsvcs.dll!boost::filesystem::path_traits::dispatch<std::wstring>(const std::string & c, std::wstring & to) Line 257 C++
appsvcs.dll!boost::filesystem::path::path<char [20]>(const char[20] & source, void * __formal) Line 168 C++
I use UTF-8 strings throughout my code, so I have configured boost::filesystem to expect UTF-8 strings as follows:
boost::nowide::nowide_filesystem();
The cause of this issue turned out to be inconsistent use of _ITERATOR_DEBUG_LEVEL. This setting does affect ABI compatibility. I was setting this flag (to 0) in my own code, but it was not set in the Boost build. The solution is to either remove the flag from one's own code, or add the flag to the Boost build by adding define=_ITERATOR_DEBUG_LEVEL=0 to the b2 arguments (from another stack overflow answer).
I want to add the mysql connection with the pcap loop which I am using in the code
MYSQL *con;
u_char *my_arguments = con;
pcap_loop(handle, total_packet_count, my_packet_handler, my_arguments);
but it is giving error
warning: initialization from incompatible pointer type
[-Wincompatible-pointer-types]
u_char *my_arguments = con;^~~
SO what should I do help is needed please
When I am directly putting value of con in pcap loop like pcap_loop(handle, total_packet_count, my_packet_handler, con); it is showing new error
Error is
passing argument 4 of ‘pcap_loop’ from incompatible pointer type
[-Wincompatible-pointer-types]
pcap_loop(handle, total_packet_count, my_packet_handler, con);
note: expected ‘u_char * {aka unsigned char *}’ but argument is of type ‘MYSQL * {aka struct st_mysql *}’
PCAP_API int pcap_loop(pcap_t *, int, pcap_handler, u_char *);
but I want it to be pushed in pcap loop
The "user" argument to pcap_loop(), pcap_dispatch(), and the callback probably should have been defined to be a void *, as it's a pointer to some arbitrary data that the callback understands, but it was defined to be a u_char * instead.
So you should cast the MYSQL * to u_char *:
pcap_loop(handle, total_packet_count, my_packet_handler, (u_char *)con);
I want to use a library that gives me a dynamic array. The dynamic array struct has a property void* _heap_ptr which gives the start of the array.
After having built the list, I want to access this pointer in cython (to make a copy of the array). But I cannot seem to get the pointer element from the struct.
Here is my pyx:
cimport src.clist as l
def main():
cdef l.ptr_list basic_list
cdef int i = 42
basic_list = l.create_list_size(sizeof(i), 100)
l.list_add_ptr(basic_list, &i)
cdef int* arr;
arr = basic_list._heap_ptr
for i in range(1):
print(arr[i])
This is the error message:
Error compiling Cython file:
------------------------------------------------------------
...
l.list_add_ptr(basic_list, &i)
cdef int* arr;
arr = basic_list._heap_ptr
^
------------------------------------------------------------
src/test.pyx:14:20: Cannot convert Python object to 'int *'
Error compiling Cython file:
------------------------------------------------------------
...
l.list_add_ptr(basic_list, &i)
cdef int* arr;
arr = basic_list._heap_ptr
^
------------------------------------------------------------
src/test.pyx:14:20: Storing unsafe C derivative of temporary Python reference
And my pxd:
cdef extern from "src/list.h":
ctypedef struct _list:
void* _heap_ptr
ctypedef struct ptr_list:
pass
ptr_list create_list_size(size_t size, int length)
list_destroy(ptr_list this_list)
void* list_at_ptr(ptr_list this_list, int index)
list_add_ptr(ptr_list this_list, void* value)
How can I fix my code? Why is this happening? From my investigations that error message pops up if you have forgotten to declare something as C (ie. use malloc not libc.stdlib.malloc, but I cannot see that anything similar is happening here.)
There are two issues in your code.
First: struct ptr_list has no members and thus no member _heap_ptr. It probably should have been
ctypedef struct ptr_list:
void* _heap_ptr
Cython's error message is not really helpful here, but as you said it pops up usually when a C-declaration is forgotten.
Second: you need to cast from void * to int * explicitly:
arr = <int*>basic_list._heap_ptr
Here is my code:
#include<stdio.h>
#include<pcap.h>
void pcapdump(u_char* argument,const struct pcap_pkthdr* packet_header,const u_char* packet_content);
int main()
{
int i=0, devid,ret;
char errbuf[PCAP_ERRBUF_SIZE];
pcap_t *handle;
bpf_u_int32 mask;
bpf_u_int32 net;
int num_packets=500;
pcap_dumper_t *p;
pcap_if_t *alldevs;
pcap_if_t *pdev;
const struct pcap_pkthdr *packet_header;
const u_char *packet_content;
ret=pcap_findalldevs(&alldevs,errbuf);
if(ret=-1)
{
printf("%s",errbuf);
};
for (pdev = alldevs;pdev;pdev=pdev->next)
printf("#%d: %s %s %s\n",++i,pdev->name,pdev->description,pdev->description);
printf("select a device: ");
scanf("%d", &devid);
pdev=alldevs;
while (--devid)
pdev=pdev->next;
printf("Selected %s \n", pdev->name);
if (pcap_lookupnet(pdev->name,&net,&mask,errbuf)==-1)
{
printf("Couldn't get netmask for device %s: %s\n", pdev->name, errbuf);
net = 0;
mask = 0;
};
handle=pcap_open_live(pdev->name,BUFSIZ,1,0,errbuf);
printf("Number of packets: %d\n", num_packets);
pcap_dump_open(handle,"/home/jiangzhongbai/capturefiles/10.pcapng");
pcap_loop(handle,num_packets,pcap_dump,NULL);
pcap_dump_close(p);
pcap_freealldevs(alldevs);
pcap_close(handle);
printf("\nCapture complete.\n");
return 0;
}
The result is
eth0 (null) (null)
wlan0 (null) (null)
nflog Linux netfilter log (NFLOG) interface Linux netfilter log (NFLOG) interface
nfqueue Linux netfilter queue (NFQUEUE) interface Linux netfilter queue (NFQUEUE) interface
any Pseudo-device that captures on all interfaces Pseudo-device that captures on all interfaces
lo (null) (null)
select a device: 2
Selected wlan0
Number of packets: 500
Segmentation fault (core dumped)
I think there is something wrong with the functionpcap_dump_open.But I don't know how to solve the problem of Segmentation fault (core dumped).Please help me.
How to solve Segmentation fault (core dumped)
If pcap_findalldevs() returns -1, don't just print an error message, quit, because alldevs isn't necessarily set to a valid value or to NULL.
Do not assume that pdev->description is non-null - only print it if it's non-null.
Assign the result of pcap_dump_open() to the variable p.
Pass p, rather than NULL, as the fourth argument to pcap_loop().
I'm trying to parse JSON using Boost's property_tree parser and from C++11 code (my system is Debian Wheezy with gcc 4.7.2 and Boost 1.49). I tried the following code based on Serializing and deserializing json with boost:
#include <map>
#include <sstream>
#include <boost/property_tree/ptree.hpp>
#include <boost/property_tree/json_parser.hpp>
using boost::property_tree::ptree; using boost::property_tree::read_json; using boost::property_tree::write_json;
void example() {
// Write json.
ptree pt;
pt.put ("foo", "bar");
std::ostringstream buf;
write_json (buf, pt, false);
std::string json = buf.str(); // {"foo":"bar"}
// Read json.
ptree pt2;
std::istringstream is (json);
read_json (is, pt2);
std::string foo = pt2.get<std::string> ("foo");
}
If I compile this with g++ -std=c++03 -c' everything is fine. However, I also want to use C++11 features (which the code in the linked thread actually does!). But withg++ -std=c++11 -c' I get compile errors:
In file included from /usr/include/boost/property_tree/json_parser.hpp:14:0,
from test.cpp:4:
/usr/include/boost/property_tree/detail/json_parser_read.hpp: In instantiation of ‘void boost::property_tree::json_parser::context<Ptree>::a_literal_val::operator() (boost::property_tree::json_parser::context<Ptree>::It, boost::property_tree::json_parser::context<Ptree>::It) const [with Ptree = boost::property_tree::basic_ptree<std::basic_string<char>, std::basic_string<char> >; boost::property_tree::json_parser::context<Ptree>::It = __gnu_cxx::__normal_iterator<char*, std::vector<char, std::allocator<char> > >]’:
/usr/include/boost/spirit/home/classic/core/scanner/scanner.hpp:148:13: required from ‘static void boost::spirit::classic::attributed_action_policy<boost::spirit::classic::nil_t>::call(const ActorT&, boost::spirit::classic::nil_t, const IteratorT&, const IteratorT&) [with ActorT = boost::property_tree::json_parser::context<boost::property_tree::basic_ptree<std::basic_string<char>, std::basic_string<char> > >::a_literal_val; IteratorT = __gnu_cxx::__normal_iterator<char*, std::vector<char, std::allocator<char> > >]’
/usr/include/boost/spirit/home/classic/core/scanner/scanner.hpp:163:13: required from ‘void boost::spirit::classic::action_policy::do_action(const ActorT&, AttrT&, const IteratorT&, const IteratorT&) const [with ActorT = boost::property_tree::json_parser::context<boost::property_tree::basic_ptree<std::basic_string<char>, std::basic_string<char> > >::a_literal_val; AttrT = boost::spirit::classic::nil_t; IteratorT = __gnu_cxx::__normal_iterator<char*, std::vector<char, std::allocator<char> > >]’
...
test.cpp:20:1: required from here
/usr/include/boost/property_tree/detail/json_parser_read.hpp:105:17: error: no matching function for call to ‘boost::property_tree::basic_ptree<std::basic_string<char>, std::basic_string<char> >::push_back(std::pair<std::basic_string<char>, std::basic_string<char> >)’
/usr/include/boost/property_tree/detail/json_parser_read.hpp:105:17: note: candidate is:
In file included from /usr/include/boost/property_tree/ptree.hpp:516:0,
from test.cpp:3:
/usr/include/boost/property_tree/detail/ptree_implementation.hpp:362:9: note: boost::property_tree::basic_ptree<Key, Data, KeyCompare>::iterator boost::property_tree::basic_ptree<Key, Data, KeyCompare>::push_back(const value_type&) [with Key = std::basic_string<char>; Data = std::basic_string<char>; KeyCompare = std::less<std::basic_string<char> >; boost::property_tree::basic_ptree<Key, Data, KeyCompare>::value_type = std::pair<const std::basic_string<char>, boost::property_tree::basic_ptree<std::basic_string<char>, std::basic_string<char> > >]
/usr/include/boost/property_tree/detail/ptree_implementation.hpp:362:9: note: no known conversion for argument 1 from ‘std::pair<std::basic_string<char>, std::basic_string<char> >’ to ‘const value_type& {aka const std::pair<const std::basic_string<char>, boost::property_tree::basic_ptree<std::basic_string<char>, std::basic_string<char> > >&}’
How can I use Boost's read_json with C++11? Do I need a newer Boost version for this (i. e. install manually from source instead of using Wheezy's packaged one)? Is there something wrong in my code? Or is this simply not possible?
It is a known bug of older Boost versions.
You can fix it by applying the following patch:
--- json_parser_read.hpp 2013-09-01 03:55:57.000000000 +0400
+++ /usr/include/boost/property_tree/detail/json_parser_read.hpp 2013-09-01 03:56:21.000000000 +0400
## -102,7 +102,7 ##
void operator()(It b, It e) const
{
BOOST_ASSERT(c.stack.size() >= 1);
- c.stack.back()->push_back(std::make_pair(c.name, Str(b, e)));
+ c.stack.back()->push_back(std::make_pair(c.name, Ptree(Str(b, e))));
c.name.clear();
c.string.clear();
}
or with
sed -i -e 's/std::make_pair(c.name, Str(b, e))/std::make_pair(c.name, Ptree(Str(b, e)))/' json_parser_read.hpp