[PATCH] D21034: [sanitizer] Fix build for new GLIBC msghdr/cmsghdr definition

[Adhemerval Zanella via llvm-commits]

zatrazz added inline comments.

================
Comment at: lib/sanitizer_common/sanitizer_platform_limits_posix.cc:1023
@@ -1015,2 +1022,3 @@
 CHECK_SIZE_AND_OFFSET(msghdr, msg_name);
+#if CHECK_SENDMSG_MEMBER
 CHECK_SIZE_AND_OFFSET(msghdr, msg_namelen);
----------------
zatrazz wrote:
> eugenis wrote:
> > zatrazz wrote:
> > > eugenis wrote:
> > > > You are disabling the test on older glibc. Why? It used to work just fine.
> > > > 
> > > That's not its intention, __GLIBC_PREREQ will only set to 0 if is not yet defined (mainly when it is built using interposed features.h that do not define it). 
> > Could you elaborate? What is this "interposed features.h" configuration, and why does it fail this test? This indicates that the struct definition does not match the system, which means certain interceptors are broken. Can it be fixed?
> And now I realize my mistake here, I will fix it.
Sorry if I was not clear enough, this part is trying to 'fix' a build for gcc libsanitizer build (where it does not define __GLIBC_PREREQ due the interposed features.h header). Now I realize this piece is should be in llvm compiler-rt and I will remove it.


Repository:
  rL LLVM

http://reviews.llvm.org/D21034