From de870d7f9f36b3e68f280057851a4585a67ab219 Mon Sep 17 00:00:00 2001 From: Sergei Trofimovich Date: Tue, 14 Jan 2020 23:15:01 +0000 Subject: [PATCH] ei_portio.h: avoid ODR violation of 'ei_default_socket_callbacks' Noticed as a build failure against fresh gcc-master: ``` LD otp/lib/erl_interface/bin/x86_64-unknown-linux-gnu/erl_call ld: otp/lib/erl_interface/obj/x86_64-unknown-linux-gnu/libei.a(eirecv.o):otp/lib/erl_interface/src/misc/ei_portio.h:50: multiple definition of `ei_default_socket_callbacks'; otp/lib/erl_interface/obj/x86_64-unknown-linux-gnu/libei.a(ei_connect.o):otp/lib/erl_interface/src/misc/ei_portio.h:50: first defined here ld: otp/lib/erl_interface/obj/x86_64-unknown-linux-gnu/libei.a(send.o):otp/lib/erl_interface/src/misc/ei_portio.h:50: multiple definition of `ei_default_socket_callbacks'; otp/lib/erl_interface/obj/x86_64-unknown-linux-gnu/libei.a(ei_connect.o):otp/lib/erl_interface/src/misc/ei_portio.h:50: first defined here ld: otp/lib/erl_interface/obj/x86_64-unknown-linux-gnu/libei.a(send_reg.o):otp/lib/erl_interface/src/misc/ei_portio.h:50: multiple definition of `ei_default_socket_callbacks'; otp/lib/erl_interface/obj/x86_64-unknown-linux-gnu/libei.a(ei_connect.o):otp/lib/erl_interface/src/misc/ei_portio.h:50: first defined here ld: otp/lib/erl_interface/obj/x86_64-unknown-linux-gnu/libei.a(epmd_port.o):otp/lib/erl_interface/src/misc/ei_portio.h:50: multiple definition of `ei_default_socket_callbacks'; otp/lib/erl_interface/obj/x86_64-unknown-linux-gnu/libei.a(ei_connect.o):otp/lib/erl_interface/src/misc/ei_portio.h:50: first defined here ld: otp/lib/erl_interface/obj/x86_64-unknown-linux-gnu/libei.a(ei_portio.o):otp/lib/erl_interface/src/misc/ei_portio.h:50: multiple definition of `ei_default_socket_callbacks'; otp/lib/erl_interface/obj/x86_64-unknown-linux-gnu/libei.a(ei_connect.o):otp/lib/erl_interface/src/misc/ei_portio.h:50: first defined here collect2: error: ld returned 1 exit status make[3]: *** [x86_64-unknown-linux-gnu/Makefile:669: otp/lib/erl_interface/bin/x86_64-unknown-linux-gnu/erl_call] Error 1 ``` The failure looks legitimate: `ei_default_socket_callbacks` is a struct defined in 'ei_portio.h' and in 'ei_portio.c'. The change flips 'ei_portio.h' definition to declaration. gcc-10 will change the default from -fcommon to fno-common: https://gcc.gnu.org/PR85678. The error also happens if CFLAGS=-fno-common passed explicitly. Signed-off-by: Sergei Trofimovich Patch taken from upstream: https://github.com/erlang/otp/commit/de870d7f9f36b3e68f280057851a4585a67ab219 Signed-off-by: Heiko Thiery --- lib/erl_interface/src/misc/ei_portio.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/erl_interface/src/misc/ei_portio.h b/lib/erl_interface/src/misc/ei_portio.h index 84ebc5039a..5172d085b4 100644 --- a/lib/erl_interface/src/misc/ei_portio.h +++ b/lib/erl_interface/src/misc/ei_portio.h @@ -47,7 +47,7 @@ int ei_writev_fill_ctx_t__(ei_socket_callbacks *cbs, void *ctx, const struct iov int ei_socket_callbacks_have_writev__(ei_socket_callbacks *cbs); #endif -ei_socket_callbacks ei_default_socket_callbacks; +extern ei_socket_callbacks ei_default_socket_callbacks; #define EI_FD_AS_CTX__(FD) \ ((void *) (long) (FD)) -- 2.20.1