CefExecuteProcess fails with hash check CEF_API_HASH_PLATFO

[miro]

Hi
when start our application we load cef etc. but the cef process cant be created and fails in function "CefExecuteProcess " in file "libcef_dll_wrapper.cc" in line 69:

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CEF_GLOBAL int CefExecuteProcess(const CefMainArgs& args,
                                 CefRefPtr<CefApp> application,
                                 void* windows_sandbox_info) {
  const char* api_hash = cef_api_hash(0);
  if (strcmp(api_hash, CEF_API_HASH_PLATFORM)) { // <-- hash value
    // The libcef API hash does not match the current header API hash.
    DCHECK(false); // <-- check failed
    return 0;
  }

What can cause that our hash value is not set properly, i have nothing in the log files about build errors etc and we never had this issue before.
Where is the CEF_API_HASH_PLATFORM value set, is the download maybe not successfull or the build process?

Thanks
Miro

[magreenblatt]

You likely have a mismatch between libcef.dll version and libcef_dll_wrapper build.

[miro]

Hello,
I would like to confirm that you are right and the versions were not the same, I had other earlier version of the DLL but now after rebuild the CEF and ensuring that the same DLL's are used everywhere this check problem doesnt occur anymore
and CefExecuteProcess doesnt fail anymore.

But few lines later i have a new problem with CefInitialize(...), in file cef_scoped_refptr.h:
Branch 5993, OS Win10 64bit, all this works previous before update to this new branch.

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m_cefApp = new ClientApp();
// arguments
CefMainArgs main_args(GetModuleHandle(nullptr));
void* sandbox_info = nullptr;
// values for settings are also set
m_bInitialized = CefInitialize(main_args, settings, m_cefApp.get(), sandbox_info);
// Failed in file cef_scoped_refptr.h in this lines:
// static
template <typename T>
void scoped_refptr<T>::Release(T* ptr) {
  ptr->Release();
}


It would be great help if someone can help to continue to use CEF.
Thanks for any help
miro

[magreenblatt]

How type is the |m_cefApp| variable? It should be a CefRefPtr<>.

[miro]

Hi,
yes its exactly like your hint:
ClientApp is derived from CefApp and defined like this:
CefRefPtr<ClientApp>m_cefApp;
Here bit more from callstack:

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// From the file: cef_scoped_refptr.h line 266:
  ~scoped_refptr() {
    static_assert(!base::cef_subtle::IsRefCountPreferenceOverridden(
                      static_cast<T*>(nullptr), static_cast<T*>(nullptr)),
                  "It's unsafe to override the ref count preference."
                  " Please remove REQUIRE_ADOPTION_FOR_REFCOUNTED_TYPE"
                  " from subclasses.");
    if (ptr_) {
      Release(ptr_);
    }
  }


and same file:

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// From the file: cef_scoped_refptr.h line 365:
// static
template <typename T>
void scoped_refptr<T>::Release(T* ptr) {
  ptr->Release(); // <-- line where the crash occurs
}


Did someone have also this issues, or know how to fix this? This is code which never make any problems before.

Thanks for any help
miro

[ndesktop]

Not sure how your code looks, but I derive my ClientApp class from CefApp, but stored as CefRefPtr<CefApp>, not CefRefPtr<ClientApp>.

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CefRefPtr<CefApp> app = new ClientApp;

Also, TheApp class does have refcounting:

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IMPLEMENT_REFCOUNTING(ClientApp);

Maybe is one of those two giving you trouble? It sounds like a combination of ClientApp::AddRef and CefApp::Release or something like that.

[miro]

Hello
@ndesktop thanks for your suggestion, i change it like your example but the issue is the same, no diff.
Sorry i could not answer earlier.
CefInitialize always return 0 and the crash is on the same code line like in my previous post.

// From the file: cef_scoped_refptr.h line 365:
// static
template <typename T>
void scoped_refptr<T>::Release(T* ptr) {
ptr->Release(); // <-- line where the crash occurs
}

Just to mention that our implementation works well since 2018 without significant issues,
so im somehow sure that our last steps which is creating distribution and following with cmke creating binaries is something broken in our scripts, i will check that now first before and test again.

regards
miro