use more reasonable install prefix when compiling natively on Windows

cmake/CMakeLists.txt

@@ -36,7 +36,11 @@ find_package(Git)
 
 # by default, install into $HOME/.local (not /usr/local), so that no root access (and sudo!!) is needed
 if(CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT)
-  set(CMAKE_INSTALL_PREFIX "$ENV{HOME}/.local" CACHE PATH "Default install path" FORCE)
+  if((CMAKE_SYSTEM_NAME STREQUAL "Windows") AND (NOT CMAKE_CROSSCOMPILING))
+    set(CMAKE_INSTALL_PREFIX "$ENV{USERPROFILE}/LAMMPS" CACHE PATH "Default install path" FORCE)
+  else()
+    set(CMAKE_INSTALL_PREFIX "$ENV{HOME}/.local" CACHE PATH "Default install path" FORCE)
+  endif()
 endif()
 
 # If enabled, no need to use LD_LIBRARY_PATH / DYLD_LIBRARY_PATH when installed

src/my_pool_chunk.cpp

@@ -13,6 +13,8 @@
 
 #include "my_pool_chunk.h"
 
+#include <cstdlib>
+
 #if defined(LMP_INTEL) && !defined(LAMMPS_MEMALIGN) && !defined(_WIN32)
 #define LAMMPS_MEMALIGN 64
 #endif