bpf: allow BSS symbols to be global symbols

Prior to this, a BSS declaration such as:

  int foo;
  static int bar;

Generates:

  .global foo
  .local  foo
  .comm   foo,4,4
  .local  bar
  .comm	  bar,4,4

Creating symbols:

  0000000000000000 b foo
  0000000000000004 b bar

Both symbols are local. However, libbpf bpf_object__variable_offset
rquires symbols to be STB_GLOBAL & STT_OBJECT for data section lookup.
This patch makes the same declaration generate:

  .global foo
  .type   foo, @object
  .lcomm  foo,4,4
  .local  bar
  .comm   bar,4,4

Creating symbols:

  0000000000000000 B foo
  0000000000000004 b bar

And libbpf will be okay with looking up the global symbol "foo".

2021-04-22  YiFei Zhu  <zhuyifei1999@gmail.com>

gcc/

	* config/bpf/bpf.h (ASM_OUTPUT_ALIGNED_BSS): Use .type and .lcomm.

0 files changed, 0 insertions, 0 deletions