update to V2.2pre1 and fix meson build

meson.build

@@ -3,7 +3,7 @@
 #
 # (c) Robert Izzard 12/11/2020
 #
-# Known to work with binary_c 2.1.7 using gcc and clang.
+# Known to work with binary_c 2.2.pre1 using gcc and clang.
 #
 # Supporting scripts are in the meson directory of binary_c.
 #
@@ -45,7 +45,7 @@ project(
         'cpp_std=gnu++17',
         'b_asneeded=false', # required on some platforms
     ],
-    version : '2.1.7', # should agree with binary_c_version.h
+    version : '2.2pre1', # should agree with binary_c_version.h
 )
 
 ############################################################
@@ -303,7 +303,7 @@ int main(int argc,char **argv)
 # version: exit if not!
 #
 if binary_c_version != meson.project_version()
-    error('binary_c_version and meson.project_version are not the same : they should be!')
+    error('binary_c_version '+binary_c_version+' and meson.project_version '+meson.project_version()+' are not the same : they should be!')
 else
     message('binary_c version is ' + binary_c_version)
 endif