From 9fa40314fcfd19d2e09459faeb480d213af56324 Mon Sep 17 00:00:00 2001 From: Adam Cozzette Date: Wed, 8 Mar 2017 11:25:48 -0800 Subject: Ruby: wrap calls to memcpy so that gem is compatible with pre-2.14 glibc This commit adds a __wrap_memcpy function and a linker flag to use that in place of memcpy for our Ruby gem C extension. This allows us to always use the 2.2.5 version of memcpy, making it possible to use the gem on distributions with pre-2.14 versions of glibc. Before this change: $ objdump -T protobuf_c.so | grep memcpy 0000000000000000 DF *UND* 0000000000000000 GLIBC_2.3.4 __memcpy_chk 0000000000000000 DF *UND* 0000000000000000 GLIBC_2.14 memcpy After: $ objdump -T protobuf_c.so | grep memcpy 0000000000000000 DF *UND* 0000000000000000 GLIBC_2.2.5 memcpy 0000000000000000 DF *UND* 0000000000000000 GLIBC_2.3.4 __memcpy_chk 0000000000042450 g DF .text 0000000000000005 Base __wrap_memcpy This is based on gRPC's solution to a similar problem: https://github.com/grpc/grpc/blob/5098508d2d41a116113f7e333c516cd9ef34a943/src/core/lib/support/wrap_memcpy.c This fixes issue #2783. --- ruby/ext/google/protobuf_c/extconf.rb | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'ruby/ext/google/protobuf_c/extconf.rb') diff --git a/ruby/ext/google/protobuf_c/extconf.rb b/ruby/ext/google/protobuf_c/extconf.rb index b368dcc6..0886e607 100644 --- a/ruby/ext/google/protobuf_c/extconf.rb +++ b/ruby/ext/google/protobuf_c/extconf.rb @@ -4,7 +4,14 @@ require 'mkmf' $CFLAGS += " -std=c99 -O3 -DNDEBUG" + +if RUBY_PLATFORM =~ /linux/ + # Instruct the linker to point memcpy calls at our __wrap_memcpy wrapper. + $LDFLAGS += " -Wl,-wrap,memcpy" +end + $objs = ["protobuf.o", "defs.o", "storage.o", "message.o", - "repeated_field.o", "map.o", "encode_decode.o", "upb.o"] + "repeated_field.o", "map.o", "encode_decode.o", "upb.o", + "wrap_memcpy.o"] create_makefile("google/protobuf_c") -- cgit v1.2.3