Patch glibc to fix a regression that causes problems with valgrind

[Douglas R. Reno]

While I was taking a look at the tests (and a runtime problem) from a recent build of Valgrind I did on my glibc-2.42 test system, I noticed a problem with DRD. I found the following branch in the glibc-2.42 branch upstream:

​https://sourceware.org/git/?p=glibc.git;a=commit;h=fd18059c0fcf5568db3688da47403b663cf91c5e

There are some other changes here that we might want to consider, but at the very least I'd like the above commit in 12.4. The rest of the changes made since 2.42 have been released can be seen here: ​https://sourceware.org/git/?p=glibc.git;a=shortlog;h=refs/heads/release/2.42/master

[Bruce Dubbs]

Fixed at commit 8d4ccb8a9a.