commit	df4d2000a22db673a788b8e57e8e7c0cc3cee777	[log] [tgz]
author	Leonard Chan <leonardchan@google.com>	Fri Oct 04 01:53:04 2019
committer	Commit Bot <commit-bot@chromium.org>	Fri Oct 04 10:58:16 2019
tree	eed6c88f2637fe318a03ea0a9fed4e4b514d6c33
parent	9c6c9c9f35dc5e1022f864a5420b53339b4e3d31 [diff]

Make vboot_version extern in header

When enabling `-fno-common` in Fuchsia, we get a bunch of linker errors
when linking futility:

```
ld.lld: error: duplicate symbol: vboot_version
>>> defined at futility.h:43 (../../third_party/vboot_reference/futility/futility.h:43)
>>>            host_x63-asan_no_detect_leaks/obj/third_party/vboot_reference/futility/futility.cmd_bdb.c.o:(vboot_version)
>>> defined at futility.h:43 (../../third_party/vboot_reference/futility/futility.h:43)
>>>            host_x64-asan_no_detect_leaks/obj/third_party/vboot_reference/futility/futility.cmd_create.c.o:(.bss.vboot_version+0x0)
```

and think this is because -fno-common places vboot_version for
unitialized global variables in the BSS section of each object file.
Making it extern instead resolves each reference to its definition in
futility/misc.c.

Change-Id: I591f07abd1f975a8a9d078bb4366e2e0861390b4
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/1839207
Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Joel Kitching <kitching@chromium.org>
Commit-Queue: Julius Werner <jwerner@chromium.org>
Tested-by: Julius Werner <jwerner@chromium.org>

diff --git a/futility/futility.h b/futility/futility.h
index 3bce110..5dc426d 100644
--- a/futility/futility.h
+++ b/futility/futility.h

@@ -41,7 +41,7 @@
 };
 
 /* What's our preferred API & data format? */
-enum vboot_version vboot_version;
+extern enum vboot_version vboot_version;
 
 /* Here's a structure to define the commands that futility implements. */
 struct futil_cmd_t {