[pjmlp]

> The first (major) console C++ SDK library is GNM/GNMX for PS4.

The major C++ SDK was the DirectX SDK for the Sega Saturn.

> Are you saying C++ games has been outliers till 201x?

Yes, the code was basically C compiled with C++ compiler.

> >What one gets is type safety

> Thanks, we've got this in C++ already.

Not when what most write is actually C compiled with C++ compiler.

> I don't know what is cache handling, to be honest, but what I meant is that, since GC moves stuff around memory

Is the ability to write cache friendly code.

If you don't want the GC to move memory around then don't allocate it via the GC.

Many GC enabled languages also allow for global statics and stack allocation. Even C# has some support here, even if it isn't comparable to what Modula-3 or D allow for.

Also there is also the possibility to just allocate it off GC heap.

> Really? You believe JIT will be on-par with a profile assisted, bruteforcing compiler, which can spend a week optimizing a single function?

No, but JITs can also make use of PGO just like AOT compilers. IBM J9 JIT and .NET RyuJIT have such support.

Also many GC enabled languages, including C# do have AOT compilers to native code code as well, it is not as JIT is the only viable approach.

[pandaman]

>The major C++ SDK was the DirectX SDK for the Sega Saturn.

a) there was no DirectX SDK for Sega Saturn. b) DirectX SDK (including one for Sega Dreamcast) is not C++. It has C++ bindings but is usable from C.

>Yes, the code was basically C compiled with C++ compiler.

You mean if I have taken that code and compiled with C compiler it worked? You realize even the DirectX C++ wrapper is not already C, right? You know classes, overloads, namespaces are not C?

>Not when what most write is actually C compiled with C++ compiler.

Could you explain exactly how this works? The C++ compiler uses ML to recognize that the code is not exactly following Alexandrescu's book and turns off typechecks? I seriously just don't understand what you mean here. I usually take "C compiled with C++ compiler", "C with classes" etc as "not enough GoF patterns for my taste" but you are making some other claim here it seems.

>If you don't want the GC to move memory around then don't allocate it via the GC.

So, why do you want GC in the first place? For types, which somehow disappeared from C++?

>No, but JITs can also make use of PGO just like AOT compilers.

How exactly does it work? The code stops executing for a week, the profiler gets run to under user credentials and then JIT finally decides?

[pjmlp]

> there was no DirectX SDK for Sega Saturn.

Broken memories, I didn't bother to search for it (Saturn vs Dreamcast).

> You mean if I have taken that code and compiled with C compiler it worked?

Of course it would, that was one of the design goals of C++.

C90 is mostly a C++98 subset, except for stronger type conversion rules (no implicit void* conversions), precedence order for operator ?: and typedef/struct namespaces.

> You realize even the DirectX C++ wrapper is not already C, right? You know classes, overloads, namespaces are not C?

Yes, but COM is also callable from C by design. Also I have seen many codebases that have restricted C++ code to calling DX APIs, with everything else being compilable by a C compiler as well.

> Could you explain exactly how this works? ...

1 - Rename .c translation units to .cpp, .cxx, .C

2 - Invoke C++ compiler on them

3 - Fix compiler errors related to semantic differences in C subset of C++

4 - Forbid use of any C++ specific feature beyond those required to use the OS SDK.

> So, why do you want GC in the first place? For types, which somehow disappeared from C++?

Productivity.

> How exactly does it work? The code stops executing for a week, the profiler gets run to under user credentials and then JIT finally decides?

PGO data generated by the JIT compiler gets updated after each application execution and is used as input for optimization selection just like in an AOT compiler by a multi-stage compiler.

Feel free to read Android 7 ART source code to learn how about a possible implementation.

[pandaman]

>Of course it would, that was one of the design goals of C++. >C90 is mostly a C++98 subset, except for stronger type conversion rules (no implicit void* conversions), precedence order for operator ?: and typedef/struct namespaces.

I think either I don't understand something you are trying to say or you are confused. C being a subset of C++ (one of design goals) does not imply C++ is a subset of C. C++ code in general cannot be compiled with C compiler without rewriting.

>Yes, but COM is also callable from C by design. Also I have seen many codebases that have restricted C++ code to calling DX APIs, with everything else being compilable by a C compiler as well.

You have blah->Foo(bar); in C++. In C it won't compile by any design. That code has to be rewritten as blah->vtbl->Foo(blah,bar). It is not C code as you claimed. It won't compile with C compiler. It's C++.

>> Could you explain exactly how this works? ... >1 - Rename .c translation units to .cpp, .cxx, .C

I asked how type checking disappears in this process, not how you compile C with C++....

>PGO data generated by the JIT compiler gets updated after each application execution and is used as input for optimization selection just like in an AOT compiler by a multi-stage compiler.

How can a JIT compiler obtain the PGO data in the first place? Is it running under profiler all the time? You realize that you've just refuted your claim about performance not being affected, right?

[pjmlp]

You are the one not understanding what it means to pick C code and compile it with a C++ compiler, minus the semantic differences.

Should I enumerate all of them to make you happy?

> You have blah->Foo(bar); in C++. In C it won't compile by any design. That code has to be rewritten as blah->vtbl->Foo(blah,bar). It is not C code as you claimed. It won't compile with C compiler. It's C++.

Nothing prevents you to write COM calls in C++ code just like in C, blah->vtbl->Foo(blah,bar). The code won't stop compiling.

> I asked how type checking disappears in this process, not how you compile C with C++....

The whole point was about writing C like code with a C++ compiler.

> How can a JIT compiler obtain the PGO data in the first place? Is it running under profiler all the time? You realize that you've just refuted your claim about performance not being affected, right?

By using a multi-stage JIT compiler with different levels of optimization and making use of multi-cores.

99% of the applications are never able to saturate all cores to the point it matters to the overall performance.

I have always been on the Pascal and C++ side against C since the early 90's on BBS and USENET.

So this type of disbelief against better tooling is not strange to me.

Cry Engine, Unreal (C++ with GC), Unity, MonoGame, with their separation between lower level C++ and higher level languages, and the way those engines are being adopted by Sony, Nintendo, Microsoft, Amazon, Google speak for themselves.

Just like C and Pascal overtook Assembly, C++ overtook C, something else will overtake C++.

[pandaman]

Ok, you completely lost me on the point you are trying to make wrt "C compiled with C++" however I wholeheartedly agree with your penultimate paragraph.

Sony and Nintendo do not use these engines, MS might be making the new Gears with UE though, rest of their first party don't. Amazon and Google have one successful game between themselves (and that's a mobile game). All these engines bring to the industry are indies and mobile games. UE actually lost quite a lot of AAA they had in UE3 times. Epic's and Crytec's own games don't do quite well (Crytec is not even making payroll). So yeah, looks like C++ games do not have much to worry about.

[pjmlp]

> Ok, you completely lost me on the point you are trying to make wrt "C compiled with C++" however I wholeheartedly agree with your penultimate paragraph.

Use the platform C++ compiler, but write code only the language subset common to C, that could even be compiled by a plain C90 compiler.

The only exception being, wrapping C++ SDK APIs into C like wrappers.

A pattern I have seen too often.

Dismissing indies is the wrong attitude, they were the first ones to adopt C and Pascal, C++, Objective-C and nowadays C#, Swift, Java.

Sony does use C# a lot on their internal tools.

Nintendo uses Unity for prototyping.

Microsoft and Google are using Unity and Unreal a lot for their VR work.

All of them invited MonoGame developers and supported them porting MonoGame into their platforms (PS4, Switch, UWP Xbox).

C++ might not go away, people still write games in C and Assembly, but it will become that very thin bottom layer at the engine architecture diagram.

Just give it time, eventually even all major C compilers became written in C++.

[douche]

> Not when what most write is actually C compiled with C++ compiler.

Is this moving the goal posts a little bit? C++ now doesn't necessarily look anything like C++ written 20 years ago. Way back, people were writing C+, or C-with-classes, but that's what C++ was, in that era.

[pjmlp]

Not at all, just because C++11, C++14 and C++17 offer lots of improvements over C++98, doesn't mean people use them.

I can assure you that at enterprise level, every time I have to integrate C++ code with our Java or .NET stacks, it looks exactly like C++ written 20 years ago, even if it was actually written last week.

Just because C++ has been vastly improved, doesn't mean everyone using it are adopting the new features, some people rather stay in Python 2 forever.