Remove conditional check for using Boost.Process:

- Since we require a min Boost version of 1.67 as of recently (for
  Beast), we also remove the conditional checks that existed for us
  to know whether Boost.Process is available or not. We can
  always assume it is available now.
- Remove runtime checks for minimum Boost and OpenSSL versions
  since they are checked at CMake configure time.

src/ripple/app/main/Main.cpp

@@ -21,7 +21,6 @@
 #include <ripple/basics/Log.h>
 #include <ripple/protocol/digest.h>
 #include <ripple/app/main/Application.h>
-#include <ripple/basics/CheckLibraryVersions.h>
 #include <ripple/basics/contract.h>
 #include <ripple/basics/StringUtilities.h>
 #include <ripple/basics/Sustain.h>
@@ -47,6 +46,7 @@
 
 #include <google/protobuf/stubs/common.h>
 
+#include <boost/process.hpp>
 #include <boost/program_options.hpp>
 #include <boost/version.hpp>
 
@@ -60,14 +60,6 @@
 #include <sys/timeb.h>
 #endif
 
-#if BOOST_VERSION >= 106400
-#define HAS_BOOST_PROCESS 1
-#endif
-
-#if HAS_BOOST_PROCESS
-#include <boost/process.hpp>
-#endif
-
 namespace po = boost::program_options;
 
 namespace ripple {
@@ -235,9 +227,7 @@ static int runUnitTests(
     if (ipv4)
         ripple::test::envUseIPv4 = true;
 
-#if HAS_BOOST_PROCESS
     if (!child && num_jobs == 1)
-#endif
     {
         multi_runner_parent parent_runner;
 
@@ -249,7 +239,6 @@ static int runUnitTests(
             return EXIT_FAILURE;
         return EXIT_SUCCESS;
     }
-#if HAS_BOOST_PROCESS
     if (!child)
     {
         multi_runner_parent parent_runner;
@@ -299,16 +288,12 @@ static int runUnitTests(
             return EXIT_FAILURE;
         return EXIT_SUCCESS;
     }
-#endif
 }
 
 //------------------------------------------------------------------------------
 
 int run (int argc, char** argv)
 {
-    // Make sure that we have the right OpenSSL and Boost libraries.
-    version::checkLibraryVersions();
-
     using namespace std;
 
     beast::setCurrentThreadName ("rippled: main");
@@ -396,10 +381,8 @@ int run (int argc, char** argv)
         "Force unit test log message output. Only useful in combination with "
         "--quiet, in which case log messages will print but suite/case names "
         "will not.")
-#if HAS_BOOST_PROCESS
     ("unittest-jobs", po::value <std::size_t> (),
         "Number of unittest jobs to run in parallel (child processes).")
-#endif
     ;
 
     // These are hidden options, not intended to be shown in the usage/help message
@@ -465,11 +448,9 @@ int run (int argc, char** argv)
 
         std::size_t numJobs = 1;
         bool unittestChild = false;
-#if HAS_BOOST_PROCESS
         if (vm.count("unittest-jobs"))
             numJobs = std::max(numJobs, vm["unittest-jobs"].as<std::size_t>());
         unittestChild = bool (vm.count("unittest-child"));
-#endif
 
         return runUnitTests(
             vm["unittest"].as<std::string>(), argument,
@@ -483,7 +464,6 @@ int run (int argc, char** argv)
     }
     else
     {
-#if HAS_BOOST_PROCESS
         if (vm.count("unittest-jobs"))
         {
             // unittest jobs only makes sense with `unittest`
@@ -491,7 +471,6 @@ int run (int argc, char** argv)
             std::cerr << "To run the unit tests the '--unittest' option must be present.\n";
             return 1;
         }
-#endif
     }
 
     auto config = std::make_unique<Config>();
@@ -727,8 +706,8 @@ int main (int argc, char** argv)
         "GCC version 5.1.0 or later is required to compile rippled.");
 #endif
 
-    static_assert (BOOST_VERSION >= 105700,
-        "Boost version 1.57 or later is required to compile rippled");
+    static_assert (BOOST_VERSION >= 106700,
+        "Boost version 1.67 or later is required to compile rippled");
 
     //
     // These debug heap calls do nothing in release or non Visual Studio builds.