Fix ODR violation from geneated mechanisms. (#1220)

* Put generated mechanisms for each built-in catalogue in their own namespace.

mechanisms/CMakeLists.txt

@@ -20,12 +20,12 @@ build_modules(
         SOURCE_DIR "${bbp_mod_srcdir}"
         DEST_DIR "${mech_dir}"
         ${external_modcc}
-        MODCC_FLAGS -t cpu -t gpu ${ARB_MODCC_FLAGS}
+        MODCC_FLAGS -t cpu -t gpu ${ARB_MODCC_FLAGS} -N arb::bbp_catalogue
         GENERATES .hpp _cpu.cpp _gpu.cpp _gpu.cu
         TARGET build_catalogue_bbp_mods)
 
 set(bbp_catalogue_source ${CMAKE_CURRENT_BINARY_DIR}/bbp_catalogue.cpp)
-set(bbp_catalogue_options -A arbor -I ${mech_dir} -o ${bbp_catalogue_source} -B multicore -C bbp)
+set(bbp_catalogue_options -A arbor -I ${mech_dir} -o ${bbp_catalogue_source} -B multicore -C bbp -N arb::bbp_catalogue)
 if(ARB_WITH_GPU)
     list(APPEND bbp_catalogue_options -B gpu)
 endif()
@@ -60,12 +60,12 @@ build_modules(
     SOURCE_DIR "${allen_mod_srcdir}"
     DEST_DIR "${mech_dir}"
     ${external_modcc}
-    MODCC_FLAGS -t cpu -t gpu ${ARB_MODCC_FLAGS}
+    MODCC_FLAGS -t cpu -t gpu ${ARB_MODCC_FLAGS} -N arb::allen_catalogue
     GENERATES .hpp _cpu.cpp _gpu.cpp _gpu.cu
     TARGET build_catalogue_allen_mods)
 
 set(allen_catalogue_source ${CMAKE_CURRENT_BINARY_DIR}/allen_catalogue.cpp)
-set(allen_catalogue_options -A arbor -I ${mech_dir} -o ${allen_catalogue_source} -B multicore -C allen)
+set(allen_catalogue_options -A arbor -I ${mech_dir} -o ${allen_catalogue_source} -B multicore -C allen -N arb::allen_catalogue)
 if(ARB_WITH_GPU)
     list(APPEND allen_catalogue_options -B gpu)
 endif()
@@ -100,12 +100,12 @@ build_modules(
     SOURCE_DIR "${default_mod_srcdir}"
     DEST_DIR "${mech_dir}"
     ${external_modcc}
-    MODCC_FLAGS -t cpu -t gpu ${ARB_MODCC_FLAGS}
+    MODCC_FLAGS -t cpu -t gpu ${ARB_MODCC_FLAGS} -N arb::default_catalogue
     GENERATES .hpp _cpu.cpp _gpu.cpp _gpu.cu
     TARGET build_catalogue_default_mods)
 
 set(default_catalogue_source ${CMAKE_CURRENT_BINARY_DIR}/default_catalogue.cpp)
-set(default_catalogue_options -A arbor -I ${mech_dir} -o ${default_catalogue_source} -B multicore -C default)
+set(default_catalogue_options -A arbor -I ${mech_dir} -o ${default_catalogue_source} -B multicore -C default -N arb::default_catalogue)
 if(ARB_WITH_GPU)
     list(APPEND default_catalogue_options -B gpu)
 endif()

mechanisms/generate_catalogue

@@ -62,6 +62,14 @@ def parse_arguments():
         metavar = 'BACKEND',
         help = 'register implementations for back-end %(metavar)s')
 
+    group.add_argument(
+        '-N', '--namespace',
+        default = [],
+        action = 'append',
+        dest = 'namespaces',
+        metavar = 'NAMESPACE',
+        help = 'add %(metavar)s to list of implicitly included namespaces')
+
     group.add_argument(
         '-C', '--catalogue',
         default = 'default',
@@ -83,7 +91,7 @@ def parse_arguments():
     return vars(parser.parse_args())
 
 
-def generate(catalogue, modpfx='', arbpfx='', modules=[], backends=[], **rest):
+def generate(catalogue, modpfx='', arbpfx='', modules=[], backends=[], namespaces=[], **rest):
     src = string.Template(\
 r'''// Automatically generated by:
 // $cmdline
@@ -91,6 +99,7 @@ r'''// Automatically generated by:
 #include <${arbpfx}mechcat.hpp>
 $backend_includes
 $module_includes
+$using_namespace
 
 namespace arb {
 
@@ -119,6 +128,8 @@ const mechanism_catalogue& global_${catalogue}_catalogue() {
         cmdline=" ".join(sys.argv),
         arbpfx=arbpfx,
         catalogue=catalogue,
+        using_namespace = indent(0,
+            ['using namespace {};'.format(n) for n in namespaces]),
         backend_includes = indent(0,
             # ['#include <{}backends/{}/fvm.hpp>'.format(arbpfx, b) for b in backends]),
             ['#include "backends/{}/fvm.hpp"'.format(b) for b in backends]),