Flex output missing from 9.1a4 tarballs?

I'm seeing this failure on a build machine with an old (and therefore
unusable) version of flex:

gcc -O2 -Wall -Wmissing-prototypes -Wpointer-arith
-Wdeclaration-after-statement -Wendif-labels -Wformat-security
-fno-strict-aliasing -fwrapv -I../../../src/include -D_GNU_SOURCE
-I/usr/local/include/libxml2 -I/usr/local/include -c -o basebackup.o
basebackup.c
/usr/bin/bison -d -o repl_gram.c repl_gram.y
***
ERROR: `flex' is missing on your system. It is needed to create the
file `repl_scanner.c'. You can either get flex from a GNU mirror site
or download an official distribution of PostgreSQL, which contains
pre-packaged flex output.
***
make[3]: *** [repl_scanner.c] Error 1
make[3]: Leaving directory
`/mnt/buildfarm/pginstaller/server/source/postgres.linux/src/backend/replication'
make[2]: Leaving directory
`/mnt/buildfarm/pginstaller/server/source/postgres.linux/src/backend'
make[2]: *** [replication-recursive] Error 2
make[1]: Leaving directory
`/mnt/buildfarm/pginstaller/server/source/postgres.linux/src'
make[1]: *** [all-backend-recurse] Error 2
make: *** [all-src-recurse] Error 2

Looks like we're missing the pre-build output from the tarball.

--
Dave Page
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Twitter: @pgsnake

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