Tests failing on CentOS 6

[Peter]

Getting this when attempting to build 2.3.11.3 on CentOS 6:

test-mail-cache.c:176: Assert failed: 
strcmp(str_c(str),"123\nfoo\n456\nbar\n")
         "" != "123
foo
456
bar
"
test-mail-cache.c:176: Assert failed: 
strcmp(str_c(str),"123\nfoo\n456\nbar\n")
         "" != "123
foo
456
bar
"
mail cache uncommitted lookups ....................................... : 
FAILED

Full make check output is at https://paste.centos.org/view/b48d38a9

I can provide full build logs if you want, but that's a 4M file so I'll 
provide it upon request.

For now I'm going ot have to bypass the make check stage of the build 
for CentOS 6, but I worry that the failed check could be indicative of 
something critical.


Peter