multiple declaration of "foo"

Hello, I have some newbie "C" question: I have two *.c files as part of my extension. In both I have these declarations: a.c ZEND_BEGIN_ARG_INFO_EX(arginfo_construct, ... b.c ZEND_BEGIN_ARG_INFO(arginfo_construct, ... I think it's correct because both are expanded to: static const zend_arg_info arginfo_construct[] ... and it's correct to have two symbols with same names in two "modules" - *.c files, isn't it? but some users complain for linker warnings: .libs/b.o:(.data.rel.local+0x80): multiple definition of `arginfo_construct' .libs/a.o:(.data.rel.local+0x80): first defined here /usr/lib/gcc/x86_64-pc-linux-gnu/4.3.4/../../../../x86_64-pc-linux-gnu/b in/ld: Warning: size of symbol `arginfo_construct' changed from 160 in .libs/a.o to 80 in .libs/b.o But in my OS no linker warning presented. Do you know how can I see these warnings in my OS? Regard M. Kubelik