From c79d37279156d8f2242c8f9acc6119c67aa5cf52 Mon Sep 17 00:00:00 2001
From: Rainer Orth <ro@gcc.gnu.org>
Date: Tue, 11 Jan 2022 23:50:37 +0100
Subject: [PATCH] [sanitizer_common] Only use NT_GNU_BUILD_ID in
 sanitizer_linux_libcdep.cpp if supported

D114294 <https://reviews.llvm.org/D114294> broke the Solaris buildbots:

  /opt/llvm-buildbot/home/solaris11-amd64/clang-solaris11-amd64/llvm/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp:613:29: error: use of undeclared identifier 'NT_GNU_BUILD_ID'
          if (nhdr->n_type == NT_GNU_BUILD_ID && nhdr->n_namesz == kGnuNamesz) {
                              ^

Like D107556 <https://reviews.llvm.org/D107556>, it forgot that
`NT_GNU_BUILD_ID` is an unportable GNU extension.

Fixed by making the code conditional on the definition of the macro.

Tested on `amd64-pc-solaris2.11` and `sparcv9-sun-solaris2.11`.

Differential Revision: https://reviews.llvm.org/D117051
---
 compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
index 06654ea5ea100..b025a5e4fb644 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
@@ -604,6 +604,7 @@ static int AddModuleSegments(const char *module_name, dl_phdr_info *info,
       cur_module.addAddressRange(cur_beg, cur_end, executable,
                                  writable);
     } else if (phdr->p_type == PT_NOTE) {
+#  ifdef NT_GNU_BUILD_ID
       uptr off = 0;
       while (off + sizeof(ElfW(Nhdr)) < phdr->p_memsz) {
         auto *nhdr = reinterpret_cast<const ElfW(Nhdr) *>(info->dlpi_addr +
@@ -629,6 +630,7 @@ static int AddModuleSegments(const char *module_name, dl_phdr_info *info,
         off += sizeof(*nhdr) + RoundUpTo(nhdr->n_namesz, 4) +
                RoundUpTo(nhdr->n_descsz, 4);
       }
+#  endif
     }
   }
   modules->push_back(cur_module);