Fix builds on compilers without anonymous union support

Fix builds on compilers without anonymous union support

The "Don't dereference type-punned pointers" patch introduced an anonymous
union, which older compilers do not support (or refuse to support when
-std=c99 is defined).  Add a configure check, and some wrapper defines to
repair builds on those compilers.

Signed-off-by: Steffan Karger <steffan@karger.me>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <1479060203-4472-1-git-send-email-steffan@karger.me>
URL: http://www.mail-archive.com/search?l=mid&q=1479060203-4472-1-git-send-email-steffan@karger.me
Signed-off-by: Gert Doering <gert@greenie.muc.de>