Include What You Use: #include <errno.h> where errno is used, or use DPLOG

base/files/memory_mapped_file_posix.cc

Index: base/files/memory_mapped_file_posix.cc
===================================================================
--- base/files/memory_mapped_file_posix.cc	(revision 223350)
+++ base/files/memory_mapped_file_posix.cc	(working copy)
@@ -25,7 +25,7 @@
 
   struct stat file_stat;
   if (fstat(file_, &file_stat) == kInvalidPlatformFileValue) {
-    DLOG(ERROR) << "Couldn't fstat " << file_ << ", errno " << errno;
+    DPLOG(ERROR) << "fstat " << file_;
     return false;
   }
   length_ = file_stat.st_size;
@@ -33,7 +33,7 @@
   data_ = static_cast<uint8*>(
       mmap(NULL, length_, PROT_READ, MAP_SHARED, file_, 0));
   if (data_ == MAP_FAILED)
-    DLOG(ERROR) << "Couldn't mmap " << file_ << ", errno " << errno;
+    DPLOG(ERROR) << "mmap " << file_;
 
   return data_ != MAP_FAILED;
 }