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 It should be needed only on outdated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.

llvm-svn: 282924

diff --git a/llvm/include/llvm/Config/config.h.cmake b/llvm/include/llvm/Config/config.h.cmake
index cc049ca..e0f68af 100644 (file)
--- a/llvm/include/llvm/Config/config.h.cmake
+++ b/llvm/include/llvm/Config/config.h.cmake
@@ -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}"
 

diff --git a/llvm/lib/Support/Unix/Memory.inc b/llvm/lib/Support/Unix/Memory.inc
index f3463e5..88b2a28 100644 (file)
--- a/llvm/lib/Support/Unix/Memory.inc
+++ b/llvm/lib/Support/Unix/Memory.inc
@@ -91,14 +91,6 @@ Memory::allocateMappedMemory(size_t NumBytes,
   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, const MemoryBlock* NearBlock,
   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