Revert r180599 "[sanitizer] Clear LD_PRELOAD when forking an external symbolizer."

llvm-svn: 180602

compiler-rt/lib/sanitizer_common/sanitizer_common.h

@@ -131,7 +131,6 @@ void DumpProcessMap();
 bool FileExists(const char *filename);
 const char *GetEnv(const char *name);
 bool SetEnv(const char *name, const char *value);
-void UnsetEnv(const char *name);
 const char *GetPwd();
 u32 GetUid();
 void ReExec();

compiler-rt/lib/sanitizer_common/sanitizer_linux.cc

@@ -278,20 +278,6 @@ bool SetEnv(const char *name, const char *value) {
 }
 #endif
 
-void UnsetEnv(const char *name) {
-  uptr name_length = internal_strlen(name);
-  uptr last = 0;
-  while (environ[last]) last++;
-  for (uptr i = 0; environ[i]; i++)
-    if (internal_strlen(environ[i]) >= name_length + 1 &&
-        internal_strncmp(environ[i], name, name_length) == 0 &&
-        environ[i][name_length] == '=') {
-      last--;
-      environ[i] = environ[last];
-      environ[last] = 0;
-    }
-}
-
 #ifdef __GLIBC__
 
 extern "C" {

compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_linux.cc

@@ -100,11 +100,6 @@ bool StartSymbolizerSubprocess(const char *path_to_symbolizer,
     internal_close(infd[1]);
     for (int fd = getdtablesize(); fd > 2; fd--)
       internal_close(fd);
-    // If the parent tool is used as a preloadable library, do not apply it to
-    // the symbolizer.
-    // FIXME: If LD_PRELOAD contains more than one object, we should keep those
-    // that have nothing to do with us.
-    UnsetEnv("LD_PRELOAD");
     execl(path_to_symbolizer, path_to_symbolizer, (char*)0);
     internal__exit(1);
   }