Adding new features to features.cpp compiler checks.

CMakeLists.txt

@@ -25,7 +25,8 @@ message("== Report build errors to https://github.com/esseks/monicelli/issues")
 
 ## 1. Compiler sanity check
 
-try_compile(
+try_run(
+    execution_results
     supported_compiler
     ${CMAKE_CURRENT_BINARY_DIR}
     ${CMAKE_CURRENT_SOURCE_DIR}/cmake/features.cpp
@@ -44,6 +45,14 @@ if (NOT supported_compiler)
     )
 endif()
 
+if (execution_results MATCHES FAILED_TO_RUN)
+    message(FATAL_ERROR
+        "Your compiler supports the set of C++11 features we need, "
+        "but something failed.\n"
+        "Run cmake with -Dcheckfeat=1 to see the exact cause."
+    )
+endif()
+
 ## 2. Find Flex and Bison
 
 find_package(BISON REQUIRED)

cmake/features.cpp

@@ -28,6 +28,24 @@
 
 #include <vector>
 #include <string>
+#include <cassert>
+
+
+const int global_i = 0;
+
+struct TestingReferenceBinding {
+    TestingReferenceBinding(int const& ii) {
+        assert(&ii == &global_i);
+    }
+
+    void operator=(int const& ii) {
+        assert(&ii == &global_i);
+    }
+
+    void operator=(int&&) {
+        assert(false);
+    }
+};
 
 enum class Dummy {
     FOO, BAR, BAZ
@@ -37,6 +55,12 @@ class Banana {
     int yep() const noexcept {
         return 0;
     }
+
+    virtual void something() {}
+};
+
+class Phone: public Banana {
+    virtual void something() override {}
 };
 
 int main() {
@@ -49,4 +73,14 @@ int main() {
     Banana a;
     Banana b = std::move(a);
     long c = std::stol("100");
+
+    // Boost::Optional sanity check for old compilers
+    int const& iref = global_i;
+    assert(&iref == &global_i);
+
+    TestingReferenceBinding ttt = global_i;
+    ttt = global_i;
+
+    TestingReferenceBinding ttt2 = iref;
+    ttt2 = iref;
 }