drop incorrect const attribute from DirectoryExists

Since its existence in 2010 DirectoryExists was always marked with this
attribute, but for no real reason. Arguably a check for the existence of
the file is not modifying global state, so theoretically this shouldn't
be a problem. It is wrong from a logical point of view through as
between two calls the directory could be created so the promise we made
to the compiler that it could remove the second call would be wrong, so
API wise it is wrong.

It's a bit mysterious that this is only observeable on ppc64el and can be
fixed by reordering code ever so slightly, but in the end its more our
fault for adding this attribute than the compilers fault for doing
something silly based on the attribute.

LP: 1473674
(cherry picked from commit 9445fa62386c80c9822e77484d30b2109aa0f2dc)

diff --git a/apt-pkg/contrib/fileutl.h b/apt-pkg/contrib/fileutl.h
index f33f7804b0d65f1574f462c7bbbb4bffd5fe3233..9333b8d5fa6a295a593fd4721c58dbb8a8c9593f 100644 (file)
--- a/apt-pkg/contrib/fileutl.h
+++ b/apt-pkg/contrib/fileutl.h
@@ -163,7 +163,7 @@ bool RemoveFile(char const * const Function, std::string const &FileName);
 int GetLock(std::string File,bool Errors = true);
 bool FileExists(std::string File);
 bool RealFileExists(std::string File);
-bool DirectoryExists(std::string const &Path) APT_CONST;
+bool DirectoryExists(std::string const &Path);
 bool CreateDirectory(std::string const &Parent, std::string const &Path);
 time_t GetModificationTime(std::string const &Path);
 bool Rename(std::string From, std::string To);