[Bug c++/98362] New: bad file data on Windows for C++ 20 module

[Bug c++/98362] New: bad file data on Windows for C++ 20 module

[unlvsur at live dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98362

            Bug ID: 98362
           Summary: bad file data on Windows for C++ 20 module
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: unlvsur at live dot com
  Target Milestone: ---

I guess the reason is because of CRLF issue. You need to open module file with
_O_BINARY flag. Or msvcrt or ucrt will trigger them as a text stream. I guess
that is the solution

E:\mingw-w64-backup\msys64\home\unlvs\www>g++ -o main hello.cc main.cc -Ofast
-std=c++20 -s -fmodules-ts
In module imported at main.cc:1:1:
hello: error: failed to read compiled module: Bad file data
hello: note: compiled module file is 'gcm.cache/hello.gcm'
hello: fatal error: returning to the gate for a mechanical issue
compilation terminated.


hello.cc

module;
#include<cstdio>
export module hello;
export inline void greeter (char const* cstr) noexcept
{
        std::puts(cstr);
}

main.cc

import hello;
int main (void)
{
        greeter("Hello\n");
}

[Bug c++/98362] bad file data on Windows for C++ 20 module

[nathan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98362

Nathan Sidwell <nathan at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2020-12-18
             Status|UNCONFIRMED                 |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |nathan at gcc dot gnu.org

--- Comment #1 from Nathan Sidwell <nathan at gcc dot gnu.org> ---
ah, I didn't know the binary/text distinction descended below the FILE level on
windows

[Bug c++/98362] bad file data on Windows for C++ 20 module

[nathan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98362

--- Comment #2 from Nathan Sidwell <nathan at gcc dot gnu.org> ---
Created attachment 49797
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=49797&action=edit
test patch

care to try this?

[Bug c++/98362] bad file data on Windows for C++ 20 module

[unlvsur at live dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98362

--- Comment #3 from cqwrteur <unlvsur at live dot com> ---
(In reply to Nathan Sidwell from comment #2)
> Created attachment 49797 [details]
> test patch
> 
> care to try this?

Sure

BTW. Windows do provide a flag O_NOINHERIT which matches O_CLOSEXEC.

[Bug c++/98362] bad file data on Windows for C++ 20 module

[unlvsur at live dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98362

--- Comment #4 from cqwrteur <unlvsur at live dot com> ---
(In reply to Nathan Sidwell from comment #2)
> Created attachment 49797 [details]
> test patch
> 
> care to try this?

I will modify your patch and try to support O_CLOSEXEC on Windows

[Bug c++/98362] bad file data on Windows for C++ 20 module

[unlvsur at live dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98362

--- Comment #5 from cqwrteur <unlvsur at live dot com> ---
Created attachment 49798
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=49798&action=edit
Compilation Working patch. Tested on both x86_64-linux-gnu and
mingw-w64-x86_64-windows10

This also adds the support for O_CLOEXEC on Windows with the O_NOINHERIT flag.

No longer uses HOST_HAS_O_CLOEXEC macro generated by the autotool. Directly
checking O_CLOEXEC macro on that platform.

There is a new bug for libstdc++ before I could test whether module works on
windows, but this patch does not break compilation.

[Bug c++/98362] bad file data on Windows for C++ 20 module

[nathan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98362

--- Comment #6 from Nathan Sidwell <nathan at gcc dot gnu.org> ---
* 785b49434d2 2020-12-18 | c++: Fix windows binary files [PR 98362]

[Bug c++/98362] bad file data on Windows for C++ 20 module

[unlvsur at live dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98362

cqwrteur <unlvsur at live dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|ASSIGNED                    |RESOLVED

--- Comment #7 from cqwrteur <unlvsur at live dot com> ---
(In reply to Nathan Sidwell from comment #6)
> * 785b49434d2 2020-12-18 | c++: Fix windows binary files [PR 98362]

Works on Windows Confirm. Thank you!