[llvm] r282924 - Retire NEED_DEV_ZERO_FOR_MMAP. It should be needed only on outdated

[Joerg Sonnenberger via llvm-commits]

Author: joerg
Date: Fri Sep 30 15:16:01 2016
New Revision: 282924

URL: http://llvm.org/viewvc/llvm-project?rev=282924&view=rev
Log:
Retire NEED_DEV_ZERO_FOR_MMAP. It should be needed only on outdated
systems. It wasn't even hooked up in cmake, so problems on such systems
would be visible with 3.9 release already.

Modified:
    llvm/trunk/include/llvm/Config/config.h.cmake
    llvm/trunk/lib/Support/Unix/Memory.inc

Modified: llvm/trunk/include/llvm/Config/config.h.cmake
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Config/config.h.cmake?rev=282924&r1=282923&r2=282924&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Config/config.h.cmake (original)
+++ llvm/trunk/include/llvm/Config/config.h.cmake Fri Sep 30 15:16:01 2016
@@ -450,10 +450,6 @@
 /* Define to the extension used for shared libraries, say, ".so". */
 #cmakedefine LTDL_SHLIB_EXT "${LTDL_SHLIB_EXT}"
 
-/* Define if /dev/zero should be used when mapping RWX memory, or undefine if
-   its not necessary */
-#undef NEED_DEV_ZERO_FOR_MMAP
-
 /* Define to the address where bug reports for this package should be sent. */
 #cmakedefine PACKAGE_BUGREPORT "${PACKAGE_BUGREPORT}"
 

Modified: llvm/trunk/lib/Support/Unix/Memory.inc
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/Unix/Memory.inc?rev=282924&r1=282923&r2=282924&view=diff
==============================================================================
--- llvm/trunk/lib/Support/Unix/Memory.inc (original)
+++ llvm/trunk/lib/Support/Unix/Memory.inc Fri Sep 30 15:16:01 2016
@@ -91,14 +91,6 @@ Memory::allocateMappedMemory(size_t NumB
   const size_t NumPages = (NumBytes+PageSize-1)/PageSize;
 
   int fd = -1;
-#ifdef NEED_DEV_ZERO_FOR_MMAP
-  static int zero_fd = open("/dev/zero", O_RDWR);
-  if (zero_fd == -1) {
-    EC = std::error_code(errno, std::generic_category());
-    return MemoryBlock();
-  }
-  fd = zero_fd;
-#endif
 
   int MMFlags = MAP_PRIVATE |
 #ifdef HAVE_MMAP_ANONYMOUS
@@ -185,14 +177,6 @@ Memory::AllocateRWX(size_t NumBytes, con
   size_t NumPages = (NumBytes+PageSize-1)/PageSize;
 
   int fd = -1;
-#ifdef NEED_DEV_ZERO_FOR_MMAP
-  static int zero_fd = open("/dev/zero", O_RDWR);
-  if (zero_fd == -1) {
-    MakeErrMsg(ErrMsg, "Can't open /dev/zero device");
-    return MemoryBlock();
-  }
-  fd = zero_fd;
-#endif
 
   int flags = MAP_PRIVATE |
 #ifdef HAVE_MMAP_ANONYMOUS