host-mingw32.c (mingw32_gt_pch_use_address): Make object_name unique for each process.

2009-04-01  Kai Tietz  <kai.tietz@onevision.com>
            Andrey Galkin <agalkin@hypercom.com>

        PR/39492
        * config/i386/host-mingw32.c (mingw32_gt_pch_use_address):
        Make object_name unique for each process.


Co-Authored-By: Andrey Galkin <agalkin@hypercom.com>

From-SVN: r145394

gcc/ChangeLog

+2009-04-01  Kai Tietz  <kai.tietz@onevision.com>
+	    Andrey Galkin <agalkin@hypercom.com>
+
+	PR/39492
+	* config/i386/host-mingw32.c (mingw32_gt_pch_use_address):
+	Make object_name unique for each process.
+
 2009-04-01  Jakub Jelinek  <jakub@redhat.com>
 
 	PR other/39591

gcc/config/i386/host-mingw32.c

@@ -120,8 +120,19 @@ mingw32_gt_pch_use_address (void *addr, size_t size, int fd,
      namespace when running an application in a Terminal Server
      session.  This causes failure since, by default, applications 
      don't get SeCreateGlobalPrivilege. We don't need global
-     memory sharing so explicitly put object into Local namespace.  */
-   const char object_name[] = "Local\\MinGWGCCPCH";
+     memory sharing so explicitly put object into Local namespace.
+
+     There is also another issue, which appears if multiple concurrent
+     GCC processes are using PCH functionality. MapViewOfFileEx returns
+     "Access Denied" error. So we need to make the session-wide mapping
+     name unique. Let's use current process ID for that.  */
+#define OBJECT_NAME_FMT "Local\\MinGWGCCPCH-"
+
+  /* Allocate enough space for name prefix and max possible DWORD
+    hexadecimal representation.  */
+  char object_name[sizeof (OBJECT_NAME_FMT) + sizeof (DWORD) * 2];
+  snprintf (object_name, sizeof (object_name), OBJECT_NAME_FMT "%lx",
+            GetCurrentProcessId());
 
   /* However, the documentation for CreateFileMapping says that on NT4
      and earlier, backslashes are invalid in object name.  So, we need