+ Add mingw unit

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@14025 3ad0048d-3df7-0310-abae-a5850022a9f2

3 files changed, 101 insertions, 2 deletions

diff --git a/packages/gdbint/examples/mingw.pas b/packages/gdbint/examples/mingw.pas
new file mode 100644
index 0000000000..626ec3b785
--- /dev/null
+++ b/packages/gdbint/examples/mingw.pas
@@ -0,0 +1,91 @@
+unit mingw;
+{
+    This file is part of the Free Pascal Integrated Development Environment
+    Copyright (c) 2009 by Marco van de Voort
+
+    Mingw helpers. Currently mostly atexit.
+    Copied from fpmingw unit from ide directory.
+
+    See the file COPYING.FPC, included in this distribution,
+    for details about the copyright.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+ **********************************************************************}
+
+interface
+
+// mingw put atexit in binaries, so that it can have one atexit, and call it from
+// dll and .exe startup code.
+// This unit provides a similar service for when mingw code (read: libgdb and friends) are statically
+// linked to FPC.
+
+Type
+  TCFunction = function:longint cdecl; // prototype of an handler to be registered with atexit
+
+function atexit(p:TCFunction):longint; cdecl;  // export our own atexit handler
+
+implementation
+
+uses gdbint; // force dependancies that hopefully make it execute at the right moment.
+
+// prototype of atexit:
+Type
+  TAtexitFunction = function(p:TCFUnction):longint cdecl;
+
+var _imp__atexit : TAtExitFunction; Cvar; external;  // "true" atexit in mingw libs.
+
+function atexit(p:TCFunction):longint;cdecl; [public, alias : '_atexit'];
+
+begin
+  atexit:=_imp__atexit(p);  // simply route to "true" atexit
+end;
+
+procedure __cpu_features_init; cdecl; external;
+procedure _pei386_runtime_relocator; cdecl; external;
+procedure __main; cdecl;external;
+
+procedure doinit;
+// other mingw initialization. Sequence from crt1.c
+begin
+ // not (yet) done: set mingw exception handlers:
+ // SetUnhandledExceptionFilter (_gnu_exception_handler);
+  __cpu_features_init;        // load CPU features. Might be useful for debugger :-)
+
+ // fpreset; 		      // don't do this, we init our own fp mask
+
+ //  _mingw32_init_mainargs ();  // mingw doesn't handle arguments not necessary.
+ //  _mingw32_init_fmode ();     // Set default filemode. Is not done for libraries, so we don't.
+
+ // Adust references to dllimported data that have non-zero offsets.
+  _pei386_runtime_relocator;  //
+
+ // aligns stack here to 16 bytes
+
+  {From libgcc.a, __main calls global class constructors via
+      __do_global_ctors, This in turn  registers  __do_global_dtors
+      as the first entry of the app's atexit table.  We do this
+      explicitly at app startup rather than rely on gcc to generate
+      the call in main's  prologue, since main may be imported from a dll
+      which has its own __do_global_ctors.  }
+ //  __main;                   // should be libgcc initialization but this causes infinite loop.
+end;
+
+procedure _cexit; cdecl; external;
+
+procedure doatexit;
+begin
+{
+   * Perform exit processing for the C library. This means
+   * flushing output and calling 'atexit' registered functions.
+}
+ _cexit ();
+end;
+
+initialization
+  doinit;
+finalization
+  doatexit;
+end.
diff --git a/packages/gdbint/examples/symify.pp b/packages/gdbint/examples/symify.pp
index d262bf1b15..7fe38dbf6c 100644
--- a/packages/gdbint/examples/symify.pp
+++ b/packages/gdbint/examples/symify.pp
@@ -12,7 +12,11 @@
 
  **********************************************************************}
 program symify;
-uses GDBInt;
+uses
+{$ifdef USE_MINGW_GDB}
+  mingw,
+{$endif}
+  GDBInt;
 
 var
   gdb : tgdbinterface;
diff --git a/packages/gdbint/examples/testgdb.pp b/packages/gdbint/examples/testgdb.pp
index fe4bbde904..ff44911a48 100644
--- a/packages/gdbint/examples/testgdb.pp
+++ b/packages/gdbint/examples/testgdb.pp
@@ -12,7 +12,11 @@
 
  **********************************************************************}
 program testgdb;
-uses gdbcon;
+uses
+{$ifdef USE_MINGW_GDB}
+  mingw,
+{$endif}
+  gdbcon;
 var
   last,s,parafile : string;
   gdb : tgdbcontroller;