Bug 175706 – [Win] TestWebKitAPI/Tests/WTF/PriorityQueue.cpp: error C2440: 'specialization': cannot convert from 'unknown-type *' to 'bool (__cdecl *)(const unsigned int &,const unsigned int &)'

• Status: RESOLVED
• Resolution: DUPLICATE
• Component: Tools / Tests

[Fujii Hironori]

I see the following compilation error in my env.
WinCairo port, trunk@220897, Debug build, VS2015 update 3

> ------ Build started: Project: TestWTFLib, Configuration: Debug x64 ------
>   PriorityQueue.cpp
> C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(59): error C2440: 'specialization': cannot convert from 'unknown-type *' to 'bool (__cdecl *)(const unsigned int &,const unsigned int &)'
>   C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(59): note: There is no context in which this conversion is possible
> C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(79): error C2440: 'specialization': cannot convert from 'unknown-type *' to 'bool (__cdecl *)(const unsigned int &,const unsigned int &)'
>   C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(79): note: There is no context in which this conversion is possible
> C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(109): error C2440: 'specialization': cannot convert from 'unknown-type *' to 'bool (__cdecl *)(const unsigned int &,const unsigned int &)'
>   C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(109): note: There is no context in which this conversion is possible
> C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(126): error C2440: 'specialization': cannot convert from 'unknown-type *' to 'bool (__cdecl *)(const unsigned int &,const unsigned int &)'
>   C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(126): note: There is no context in which this conversion is possible
> C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(152): error C2440: 'specialization': cannot convert from 'unknown-type *' to 'bool (__cdecl *)(const unsigned int &,const unsigned int &)'
>   C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(152): note: There is no context in which this conversion is possible
> C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(178): error C2440: 'specialization': cannot convert from 'unknown-type *' to 'bool (__cdecl *)(const unsigned int &,const unsigned int &)'
>   C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(178): note: There is no context in which this conversion is possible
> C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(210): error C2440: 'specialization': cannot convert from 'unknown-type *' to 'bool (__cdecl *)(const uint64_t &,const uint64_t &)'
>   C:\webkit\ga\Tools\TestWebKitAPI\Tests\WTF\PriorityQueue.cpp(210): note: There is no context in which this conversion is possible
> ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========


VS2017 seems fine because BuildBots are green.

[Fujii Hironori]

AppleWin BuildBots are using VS2015.
It happens only in my env?

[Yusuke Suzuki]

(In reply to Fujii Hironori from comment #1)
> AppleWin BuildBots are using VS2015.
> It happens only in my env?

According to the buildbot, AppleWin buildbots use VS2015 and compiles them fine... Hmmm.

[Don Olmstead]

(In reply to Yusuke Suzuki from comment #2)
> (In reply to Fujii Hironori from comment #1)
> > AppleWin BuildBots are using VS2015.
> > It happens only in my env?
> 
> According to the buildbot, AppleWin buildbots use VS2015 and compiles them
> fine... Hmmm.

I've seen this as well with WinCairo being built on VS2015. The buildbot is 2017 and it seemed like we were close to dropping 2015 so I didn't attempt a fix.

[Fujii Hironori]

Created attachment 318614 [details]
simple test case

> C:\home\fujii\tmp>cl a.cpp
> Microsoft (R) C/C++ Optimizing Compiler Version 19.00.24215.1 for x64
> Copyright (C) Microsoft Corporation.  All rights reserved.
> 
> a.cpp
> a.cpp(15): error C2440: 'specialization': cannot convert from 'unknown-type *' to 'void (__cdecl *)(int)'
> a.cpp(15): note: There is no context in which this conversion is possible
> 
> C:\home\fujii\tmp>

[Fujii Hironori]

AppleWin BuildBot is using older version of MSVC than mine. I don't know this is relevant.

https://build.webkit.org/builders/Apple%20Win%20Release%20%28Build%29/builds/3735/steps/compile-webkit/logs/stdio/text

> -- Building for: Visual Studio 14 2015
> -- The C compiler identification is MSVC 19.0.23918.0
> -- The CXX compiler identification is MSVC 19.0.23918.0

[Fujii Hironori]

*** This bug has been marked as a duplicate of bug 176442 ***