Add -fno-common compile option

-fno-common makes sure we do not have multiple declarations of the same
global symbol across compilation units. It helps debug nasty linkage
bugs by guaranteeing that all reference to a global symbol use the same
underlying object.
It also helps avoiding benign mistakes such as declaring enum as global
objects instead of types in headers (hence the minor fixes scattered
across the source).

Change-Id: I55c16406dc54ff8a6860238b90ca990fa6b179f1
Signed-off-by: Benoît Ganne <bganne@cisco.com>

src/cmake/cpu.cmake

@@ -93,7 +93,7 @@ macro(vpp_library_set_multiarch_sources lib)
     set(l ${lib}_${VARIANT})
     add_library(${l} OBJECT ${ARGN})
     set_target_properties(${l} PROPERTIES POSITION_INDEPENDENT_CODE ON)
-    target_compile_options(${l} PUBLIC "-DCLIB_MARCH_VARIANT=${VARIANT}")
+    target_compile_options(${l} PUBLIC "-DCLIB_MARCH_VARIANT=${VARIANT}" -Wall -fno-common)
     separate_arguments(VARIANT_FLAGS)
     target_compile_options(${l} PUBLIC ${VARIANT_FLAGS})
     target_sources(${lib} PRIVATE $<TARGET_OBJECTS:${l}>)

src/cmake/library.cmake

@@ -20,7 +20,7 @@ macro(add_vpp_library lib)
   )
 
   add_library(${lib} SHARED ${ARG_SOURCES})
-  target_compile_options(${lib} PRIVATE -Wall)
+  target_compile_options(${lib} PRIVATE -Wall -fno-common)
   if(VPP_LIB_VERSION)
     set_target_properties(${lib} PROPERTIES SOVERSION ${VPP_LIB_VERSION})
   endif()

src/plugins/acl/fa_node.h

@@ -241,7 +241,7 @@ typedef enum {
 } acl_fa_next_t;
 
 
-enum
+typedef enum
 {
   ACL_FA_CLEANER_RESCHEDULE = 1,
   ACL_FA_CLEANER_DELETE_BY_SW_IF_INDEX,

src/plugins/avf/avf.h

@@ -168,7 +168,7 @@ typedef struct
 
 #define AVF_RX_VECTOR_SZ VLIB_FRAME_SIZE
 
-enum
+typedef enum
 {
   AVF_PROCESS_EVENT_START = 1,
   AVF_PROCESS_EVENT_STOP = 2,

src/plugins/memif/private.h

@@ -255,7 +255,7 @@ extern memif_main_t memif_main;
 extern vnet_device_class_t memif_device_class;
 extern vlib_node_registration_t memif_input_node;
 
-enum
+typedef enum
 {
   MEMIF_PROCESS_EVENT_START = 1,
   MEMIF_PROCESS_EVENT_STOP = 2,

src/vcl/vcl_private.h

@@ -115,7 +115,7 @@ typedef struct vcl_session_msg
   u32 flags;
 } vcl_session_msg_t;
 
-enum
+typedef enum
 {
   VCL_SESS_ATTR_SERVER,
   VCL_SESS_ATTR_CUT_THRU,

src/vnet/bfd/bfd_main.h

@@ -345,7 +345,7 @@ typedef struct
   u8 data[400];
 } bfd_input_trace_t;
 
-enum
+typedef enum
 {
   BFD_EVENT_RESCHEDULE = 1,
   BFD_EVENT_NEW_SESSION,

src/vnet/bier/bier_fmask.h

@@ -171,7 +171,7 @@ extern void bier_fmask_encode (index_t bfmi,
 /*
  * provided for fast data-path access
  */
-bier_fmask_t *bier_fmask_pool;
+extern bier_fmask_t *bier_fmask_pool;
 
 static inline bier_fmask_t *
 bier_fmask_get (u32 index)

src/vnet/bonding/node.c

@@ -21,7 +21,9 @@
 #include <vnet/snap/snap.h>
 #include <vnet/bonding/node.h>
 
+#ifndef CLIB_MARCH_VARIANT
 bond_main_t bond_main;
+#endif /* CLIB_MARCH_VARIANT */
 
 #define foreach_bond_input_error \
   _(NONE, "no error")            \

src/vnet/bonding/node.h

@@ -70,7 +70,7 @@ typedef enum
 #undef _
 } bond_load_balance_t;
 
-enum
+typedef enum
 {
   BOND_SEND_GARP_NA = 1,
 } bond_send_garp_na_process_event_t;

src/vnet/devices/pipe/pipe_api.c

@@ -36,7 +36,7 @@
 #undef vl_printfun
 
 #include <vlibapi/api_helper_macros.h>
-vpe_api_main_t vpe_api_main;
+extern vpe_api_main_t vpe_api_main;
 
 #define foreach_vpe_api_msg                                     \
   _(PIPE_CREATE, pipe_create)                                   \

src/vnet/devices/virtio/vhost_user_input.c

@@ -65,7 +65,7 @@
  */
 #define VHOST_USER_RX_COPY_THRESHOLD 64
 
-vlib_node_registration_t vhost_user_input_node;
+extern vlib_node_registration_t vhost_user_input_node;
 
 #define foreach_vhost_user_input_func_error      \
   _(NO_ERROR, "no error")  \

src/vnet/devices/virtio/vhost_user_output.c

@@ -53,7 +53,7 @@
  */
 #define VHOST_USER_TX_COPY_THRESHOLD (VHOST_USER_COPY_ARRAY_N - 40)
 
-vnet_device_class_t vhost_user_device_class;
+extern vnet_device_class_t vhost_user_device_class;
 
 #define foreach_vhost_user_tx_func_error      \
   _(NONE, "no error")  \

src/vnet/dpo/dvr_dpo.c

@@ -18,6 +18,8 @@
 #include <vnet/ip/ip.h>
 #include <vnet/ethernet/ethernet.h>
 
+dvr_dpo_t *dvr_dpo_pool;
+
 /**
  * The 'DB' of DVR DPOs.
  * There is one per-interface per-L3 proto, so this is a per-interface vector

src/vnet/dpo/dvr_dpo.h

@@ -54,7 +54,7 @@ extern void dvr_dpo_module_init(void);
 /**
  * @brief pool of all interface DPOs
  */
-dvr_dpo_t *dvr_dpo_pool;
+extern dvr_dpo_t *dvr_dpo_pool;
 
 static inline dvr_dpo_t *
 dvr_dpo_get (index_t index)

src/vnet/dpo/interface_rx_dpo.c

@@ -17,6 +17,8 @@
 #include <vnet/fib/fib_node.h>
 #include <vnet/l2/l2_input.h>
 
+interface_rx_dpo_t *interface_rx_dpo_pool;
+
 /*
  * The 'DB' of interface DPOs.
  * There is only one  per-interface per-protocol, so this is a per-interface

src/vnet/dpo/interface_rx_dpo.h

@@ -58,7 +58,7 @@ extern void interface_rx_dpo_module_init(void);
 /**
  * @brief pool of all interface DPOs
  */
-interface_rx_dpo_t *interface_rx_dpo_pool;
+extern interface_rx_dpo_t *interface_rx_dpo_pool;
 
 static inline interface_rx_dpo_t *
 interface_rx_dpo_get (index_t index)

src/vnet/dpo/l3_proxy_dpo.h

@@ -52,7 +52,7 @@ extern void l3_proxy_dpo_module_init(void);
 /**
  * @brief pool of all l3_proxy DPOs
  */
-l3_proxy_dpo_t *l3_proxy_dpo_pool;
+extern l3_proxy_dpo_t *l3_proxy_dpo_pool;
 
 static inline l3_proxy_dpo_t *
 l3_proxy_dpo_get (index_t index)

src/vnet/dpo/receive_dpo.h

@@ -59,7 +59,7 @@ extern void receive_dpo_module_init(void);
 /**
  * @brief pool of all receive DPOs
  */
-receive_dpo_t *receive_dpo_pool;
+extern receive_dpo_t *receive_dpo_pool;
 
 static inline receive_dpo_t *
 receive_dpo_get (index_t index)

src/vnet/ip/ip4_forward.c

@@ -900,7 +900,9 @@ ip4_sw_interface_add_del (vnet_main_t * vnm, u32 sw_if_index, u32 is_add)
 VNET_SW_INTERFACE_ADD_DEL_FUNCTION (ip4_sw_interface_add_del);
 
 /* Global IP4 main. */
+#ifndef CLIB_MARCH_VARIANT
 ip4_main_t ip4_main;
+#endif /* CLIB_MARCH_VARIANT */
 
 static clib_error_t *
 ip4_lookup_init (vlib_main_t * vm)

src/vnet/ip/ip6_forward.c

@@ -2074,7 +2074,9 @@ VLIB_REGISTER_NODE (ip6_mcast_midchain_node) =
 /*
  * Hop-by-Hop handling
  */
+#ifndef CLIB_MARCH_VARIANT
 ip6_hop_by_hop_main_t ip6_hop_by_hop_main;
+#endif /* CLIB_MARCH_VARIANT */
 
 #define foreach_ip6_hop_by_hop_error \
 _(PROCESSED, "pkts with ip6 hop-by-hop options") \
@@ -2102,7 +2104,7 @@ typedef struct
   u8 option_data[256];
 } ip6_hop_by_hop_trace_t;
 
-vlib_node_registration_t ip6_hop_by_hop_node;
+extern vlib_node_registration_t ip6_hop_by_hop_node;
 
 static char *ip6_hop_by_hop_error_strings[] = {
 #define _(sym,string) string,

src/vnet/ipsec/esp_encrypt.c

@@ -23,7 +23,9 @@
 #include <vnet/ipsec/ipsec.h>
 #include <vnet/ipsec/esp.h>
 
+#ifndef CLIB_MARCH_VARIANT
 ipsec_proto_main_t ipsec_proto_main;
+#endif /* CLIB_MARCH_VARIANT */
 
 #define foreach_esp_encrypt_next                   \
 _(DROP, "error-drop")                              \

src/vnet/l2/l2_learn.h

@@ -52,7 +52,7 @@ extern l2learn_main_t l2learn_main;
 
 extern vlib_node_registration_t l2fib_mac_age_scanner_process_node;
 
-enum
+typedef enum
 {
   L2_MAC_AGE_PROCESS_EVENT_START = 1,
   L2_MAC_AGE_PROCESS_EVENT_STOP = 2,

src/vnet/l2/l2_patch.c

@@ -49,7 +49,7 @@ format_l2_patch_trace (u8 * s, va_list * args)
   return s;
 }
 
-l2_patch_main_t l2_patch_main;
+static l2_patch_main_t l2_patch_main;
 
 static vlib_node_registration_t l2_patch_node;
 

src/vnet/lldp/lldp_node.h

@@ -131,7 +131,7 @@ typedef struct
   u8 data[400];
 } lldp_input_trace_t;
 
-enum
+typedef enum
 {
   LLDP_EVENT_RESCHEDULE = 1,
 } lldp_process_event_t;

src/vnet/mpls/mpls_lookup.h

@@ -23,7 +23,7 @@
 /**
  * The arc/edge from the MPLS lookup node to the MPLS replicate node
  */
-u32 mpls_lookup_to_replicate_edge;
+extern u32 mpls_lookup_to_replicate_edge;
 
 /**
  * Enum of statically configred MPLS lookup next nodes

src/vnet/session/session_lookup.h

@@ -96,7 +96,7 @@ void session_lookup_dump_rules_table (u32 fib_index, u8 fib_proto,
 void session_lookup_dump_local_rules_table (u32 fib_index, u8 fib_proto,
 					    u8 transport_proto);
 
-enum _session_rule_scope
+typedef enum _session_rule_scope
 {
   SESSION_RULE_SCOPE_GLOBAL = 1,
   SESSION_RULE_SCOPE_LOCAL = 2,