the release tarballs of binutils 2.24 and gdb 7.6 were generated with an ancient autoconf version (2.64), which causes long-fixed and nasty bugs ( https://sourceware.org/bugzilla/show_bug.cgi?id=16370 gdb bug report ) to reraise from the dead. to prevent such breakage in the future we should test for and deny running "make dist" successfully when the detected autoconf version is < 2.69.
I think the autoconf version bump in the binutils-gdb tree didn't happen until well after these releases. In binutils-gdb, the auto* output files are checked in and everyone (including make dist) is required to use the identical versions. I'm not totally sure this is the best thing to do any more, but it is current reality. So, I tend to think this bug is invalid.
.