[cmake] Check std::vector layout

cmake/modules/CheckCompiler.cmake

@@ -261,3 +261,21 @@ endif()
 if(gnuinstall)
   set(R__HAVE_CONFIG 1)
 endif()
+
+
+#---Check if the std::vector implementation is using three pointers or one pointer and two integers
+message(STATUS "Checking std::vector layout")
+try_run(RUN_CHECK_LIBCPP_VECTOR_RESULT COMPILE_CHECK_LIBCPP_VECTOR_RESULT
+      ${CMAKE_BINARY_DIR}
+      SOURCES "${CMAKE_SOURCE_DIR}/cmake/modules/check_libcpp_vector.cpp"
+      COMPILE_OUTPUT_VARIABLE COMPILE_CHECK_LIBCPP_VECTOR_OUTPUT)
+
+if(NOT COMPILE_CHECK_LIBCPP_VECTOR_RESULT)
+   message(FATAL_ERROR "Failed to compile vector layout check, "
+           "likely an issue with the compiler installation: ${COMPILE_CHECK_LIBCPP_VECTOR_OUTPUT}")
+endif()
+
+if(NOT RUN_CHECK_LIBCPP_VECTOR_RESULT EQUAL 0)
+  message(FATAL_ERROR "Size based std::vector layout is unsupported; "
+          "run result='${RUN_CHECK_LIBCPP_VECTOR_RESULT}' (1 = size based, 2 = unexpected).")
+endif()

cmake/modules/check_libcpp_vector.cpp

@@ -0,0 +1,27 @@
+#include <cstddef>
+#include <vector>
+
+#if defined(_MSC_VER)
+  #define NOINLINE __declspec(noinline)
+#else
+  #define NOINLINE __attribute__((noinline))
+#endif
+
+// Don't inline to prevent the optimizer from interfering with the test
+NOINLINE static std::size_t GetTypeErasedSize(const void *vec)
+{
+   return reinterpret_cast<const std::vector<char> *>(vec)->size();
+}
+
+int main()
+{
+   std::vector<int> v(1);
+   const auto size = GetTypeErasedSize(reinterpret_cast<const void *>(&v));
+   if (size == sizeof(int)) {
+      return 0;
+   } else if (size == 1) {
+      return 1; // New ABI
+   } else {
+      return 2; // Unexpected
+   }
+}

interpreter/cling/include/cling/Interpreter/RuntimeUniverse.h

@@ -25,6 +25,7 @@
 
 #include <cling/Interpreter/RuntimeOptions.h>
 #include "cling/Interpreter/Visibility.h"
+#include <cstddef>
 #include <new>
 
 namespace cling {

main/src/rmain.cxx

@@ -21,6 +21,7 @@
 #include "RConfigure.h"
 
 #include <cstdio>
+#include <cstdlib>
 #ifdef _MSC_VER
 #include <process.h>
 #define execv _execv

tree/treeplayer/src/TTreeFormulaManager.cxx

@@ -15,6 +15,8 @@
 #include "TError.h"
 #include "TLeafElement.h"
 
+#include <cmath>
+
 
    /** \class TTreeFormulaManager
    Used to coordinate one or more TTreeFormula objects.