host-mingw32.c (va_granularity): Make none-const.

        * config/i386/host-mingw32.c (va_granularity): Make none-const.
        (mingw32_gt_pch_alloc_granularity): Return OS' allocation
        granularity.
        (mingw32_gt_pch_use_address): Retry mapping of used address
        as multiple instances might interfer.

From-SVN: r193987

gcc/ChangeLog

 2012-11-30  Kai Tietz  <ktietz@redhat.com>
 
+	* config/i386/host-mingw32.c (va_granularity): Make none-const.
+	(mingw32_gt_pch_alloc_granularity): Return OS' allocation
+	granularity.
+	(mingw32_gt_pch_use_address): Retry mapping of used address
+	as multiple instances might interfer.
+
 	* config/i386/mingw32.h (SHARED_LIBGCC_SPEC): Synchronize with
 	cygwin-host.
 

gcc/config/i386/host-mingw32.c

@@ -27,6 +27,7 @@
 
 #define WIN32_LEAN_AND_MEAN  /* Not so important if we have windows.h.gch.  */
 #include <windows.h>
+#include <stdlib.h>
 
 static void * mingw32_gt_pch_get_address (size_t, int);
 static int mingw32_gt_pch_use_address (void *, size_t, int, size_t);
@@ -45,7 +46,7 @@ static inline void w32_error(const char*, const char*, int, const char*);
 static const size_t pch_VA_max_size  = 128 * 1024 * 1024;
 
 /* Granularity for reserving address space.  */
-static const size_t va_granularity = 0x10000;
+static size_t va_granularity = 0x10000;
 
 /* Print out the GetLastError() translation.  */ 
 static inline void
@@ -66,8 +67,14 @@ w32_error (const char* function, const char* file, int line,
 }
 
 /* Granularity for reserving address space.  */
-static size_t mingw32_gt_pch_alloc_granularity (void)
+static size_t
+mingw32_gt_pch_alloc_granularity (void)
 {
+  SYSTEM_INFO si;
+
+  GetSystemInfo (&si);
+  va_granularity = (size_t) si.dwAllocationGranularity;
+
   return va_granularity;
 }
 
@@ -114,7 +121,7 @@ mingw32_gt_pch_use_address (void *addr, size_t size, int fd,
 {
   void * mmap_addr;
   HANDLE mmap_handle;
-
+ 
   /* Apparently, MS Vista puts unnamed file mapping objects into Global
      namespace when running an application in a Terminal Server
      session.  This causes failure since, by default, applications 
@@ -132,6 +139,8 @@ mingw32_gt_pch_use_address (void *addr, size_t size, int fd,
      and earlier, backslashes are invalid in object name.  So, we need
      to check if we are on Windows2000 or higher.  */
   OSVERSIONINFO version_info;
+  int r;
+
   version_info.dwOSVersionInfoSize = sizeof (version_info);
 
   if (size == 0)
@@ -154,7 +163,6 @@ mingw32_gt_pch_use_address (void *addr, size_t size, int fd,
 		OBJECT_NAME_FMT "%lx", GetCurrentProcessId());
       object_name = local_object_name;
     }
-     
   mmap_handle = CreateFileMappingA ((HANDLE) _get_osfhandle (fd), NULL,
 				    PAGE_WRITECOPY | SEC_COMMIT, 0, 0,
 				    object_name);
@@ -164,8 +172,19 @@ mingw32_gt_pch_use_address (void *addr, size_t size, int fd,
       w32_error (__FUNCTION__,  __FILE__, __LINE__, "CreateFileMapping");
       return -1; 
     }
-  mmap_addr = MapViewOfFileEx (mmap_handle, FILE_MAP_COPY, 0, offset,
-			       size, addr);
+
+  /* Retry five times, as here might occure a race with multiple gcc's
+     instances at same time.  */
+  for (r = 0; r < 5; r++)
+   {
+      mmap_addr = MapViewOfFileEx (mmap_handle, FILE_MAP_COPY, 0, offset,
+				   size, addr);
+      if (mmap_addr == addr)
+	break;
+      if (r != 4)
+        Sleep (500);
+   }
+      
   if (mmap_addr != addr)
     {
       w32_error (__FUNCTION__, __FILE__, __LINE__, "MapViewOfFileEx");