Pin coverage tool using outdated C++ namespace

[kauwua]

Hi,

While compiling the Pin coverage tool in https://github.com/gaasedelen/lighthouse/tree/562595be9bd99e8a5dfef6017d608467f5706630/coverage/pin using the latest Pin version (4.0), I was met with the following errors:

CodeCoverage.cpp:21:28: error: ‘tr1’ in namespace ‘std’ does not name a type
   21 | using unordered_set = std::tr1::unordered_set<V>;
      |                            ^~~
CodeCoverage.cpp:24:28: error: ‘tr1’ in namespace ‘std’ does not name a type
   24 | using unordered_map = std::tr1::unordered_map<K, V>;

std::tr1 seems to be an old C++ namespace used for functionalities proposed in the C++ Technical Report 1, a lot of which were later integrated in C++11 (from what I read). The comments indicate std::tr1 was used because of Pin using an old standard lib but it seems to have been fixed.

In any case, replacing std::tr1 by std:: solved the issue and I was able to use the coverage tool on a fairly large program (on amd64 Linux).

I'm proposing this MR #161 which removes the unordered_set and unordered_map aliases, as unordered_set is unused and std::unordered_map works. It should be tested on MacOS and Windows as well however, and I'm wondering if compatiblity with older Pin versions is important (std::tr1 could be used for specific versions only).

Best,