Issue #6790 has been updated by luislavena (Luis Lavena).


nobu (Nobuyoshi Nakada) wrote:
> Seems it occurs only in x64-mingw; and does not occur when loading the DLL by x64-mswin ruby.exe.
> Needs more investigation.

Do you think this simplification is good enough?

https://github.com/luislavena/experiments/tree/master/dll-handles

DllMain is only invoked once on this example, which might indicate something going on on Ruby.

After a GDB session, seems that dln.c line 1271 (LoadLibrary) is causing x64-msvcrt-ruby200.dll be loaded again.

Will keep investigating on this.
----------------------------------------
Bug #6790: mingw-w64: rb_libruby_handle and libruby changes when extensions are loaded
https://bugs.ruby-lang.org/issues/6790#change-28443

Author: luislavena (Luis Lavena)
Status: Assigned
Priority: Normal
Assignee: nobu (Nobuyoshi Nakada)
Category: core
Target version: 2.0.0
ruby -v: ruby 2.0.0dev (2012-07-25 trunk 36527) [x64-mingw32]


=begin
Hello,

I started to look into this failure when running dl/handle tests:

 test_initialize_noargs(DL::TestHandle):
 DL::DLError: unknown symbol "rb_str_new"
     C:/Users/Worker/Jenkins/workspace/git-ruby-trunk/test/dl/test_handle.rb:110:in `[]'
     C:/Users/Worker/Jenkins/workspace/git-ruby-trunk/test/dl/test_handle.rb:110:in `test_initialize_noargs'

Above error only happens with compiled 64bits ruby.

After looking a bit more closer, it seems DllMain from libruby gets called several times when (({x64-msvcrt-ruby200.dll})) is loaded but also when extensions are loaded.

Adding some debug strings into DllMain like the following:

 diff --git a/ruby.c b/ruby.c
 index ab4b674..6d1a715 100644
 --- a/ruby.c
 +++ b/ruby.c
 @@ -315,8 +315,22 @@ static HMODULE libruby;
  BOOL WINAPI
  DllMain(HINSTANCE dll, DWORD reason, LPVOID reserved)
  {
 +    HMODULE self;
 +    char filename[MAX_PATH];
 +
      if (reason == DLL_PROCESS_ATTACH)
 -       libruby = dll;
 +    {
 +        printf("DLL_PROCESS_ATTACH\n");
 +
 +        self = GetModuleHandle(NULL);
 +        GetModuleFileName(self, filename, MAX_PATH);
 +        printf("self: %#x (%s)\n", self, filename);
 +
 +        GetModuleFileName(dll, filename, MAX_PATH);
 +        printf("dll: %#x (%s)\n", dll, filename);
 +
 +        libruby = dll;
 +    }
      return TRUE;
  }

Produces the following:

32bits compilation:

 C:\Users\Luis\Code\ruby\ruby\x86-installed>ruby -v -rdl -e "puts :ok"
 DLL_PROCESS_ATTACH
 self: 0x400000 (C:\Users\Luis\Code\ruby\ruby\x86-installed\bin\ruby.exe)
 dll: 0x66780000 (C:\Users\Luis\Code\ruby\ruby\x86-installed\bin\msvcrt-ruby200.dll)
 ruby 2.0.0dev (2012-07-25 trunk 36527) [i386-mingw32]
 ok

64bits (mingw-w64):

 C:\Users\Luis\Code\ruby\ruby\x64-installed>ruby -v -rdl -e "puts :ok"
 DLL_PROCESS_ATTACH
 self: 0x400000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\bin\ruby.exe)
 dll: 0x6f100000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\bin\x64-msvcrt-ruby200.dll)
 ruby 2.0.0dev (2012-07-25 trunk 36527) [x64-mingw32]
 DLL_PROCESS_ATTACH
 self: 0x400000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\bin\ruby.exe)
 dll: 0x1ee0000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\lib\ruby\2.0.0\x64-mingw32\enc\encdb.so)
 DLL_PROCESS_ATTACH
 self: 0x400000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\bin\ruby.exe)
 dll: 0x6aa00000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\lib\ruby\2.0.0\x64-mingw32\enc\iso_8859_1.so)
 DLL_PROCESS_ATTACH
 self: 0x400000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\bin\ruby.exe)
 dll: 0x68080000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\lib\ruby\2.0.0\x64-mingw32\enc\trans\transdb.so)
 DLL_PROCESS_ATTACH
 self: 0x400000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\bin\ruby.exe)
 dll: 0x623c0000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\lib\ruby\2.0.0\x64-mingw32\dl.so)
 DLL_PROCESS_ATTACH
 self: 0x400000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\bin\ruby.exe)
 dll: 0x63d80000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\lib\ruby\2.0.0\x64-mingw32\fiddle.so)
 DLL_PROCESS_ATTACH
 self: 0x400000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\bin\ruby.exe)
 dll: 0x6e6c0000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\lib\ruby\2.0.0\x64-mingw32\enc\utf_16le.so)
 DLL_PROCESS_ATTACH
 self: 0x400000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\bin\ruby.exe)
 dll: 0x6a340000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\lib\ruby\2.0.0\x64-mingw32\enc\trans\single_byte.so)
 DLL_PROCESS_ATTACH
 self: 0x400000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\bin\ruby.exe)
 dll: 0x1f10000 (C:\Users\Luis\Code\ruby\ruby\x64-installed\lib\ruby\2.0.0\x64-mingw32\enc\trans\utf_16_32.so)
 ok

I just tested a simple project which loads multiple DLLs and DllMain of each DLL do not get invoked several times.

Since each extension depends on (({x86-msvcrt-ruby200.dll})), perhaps that is the reason why (({DllMain})) is invoked multiple times.

Maybe there is something I'm missing? Perhaps a workaround will be set (({libruby})) only once?
=end


-- 
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