From 8a5e425a68de4d2c80ff00a97bbcb3722a4716da Mon Sep 17 00:00:00 2001
From: Kostya Serebryany <kcc@google.com>
Date: Thu, 13 Jul 2017 21:59:01 +0000
Subject: [PATCH] Fix sanitizer build against latest glibc

Summary:
libsanitizer doesn't build against latest glibc anymore, see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81066 for details.
One of the changes is that stack_t changed from typedef struct sigaltstack { ... } stack_t; to typedef struct { ... } stack_t; for conformance reasons.
And the other change is that the glibc internal __need_res_state macro is now ignored, so when doing
```
#define __need_res_state
#include <resolv.h>
```
the effect is now the same as just
```
#include <resolv.h>
```
and thus one doesn't get just the
```
struct __res_state { ... };
```
definition, but newly also the
```
extern struct __res_state *__res_state(void) __attribute__ ((__const__));
```
prototype.  So __res_state is no longer a type, but a function.

Reviewers: kcc, ygribov

Reviewed By: kcc

Subscribers: kubamracek

Differential Revision: https://reviews.llvm.org/D35246

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@307969 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/sanitizer_common/sanitizer_linux.cc                      | 3 +--
 lib/sanitizer_common/sanitizer_linux.h                       | 4 +---
 lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc | 2 +-
 lib/tsan/rtl/tsan_platform_linux.cc                          | 2 +-
 4 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/projects/compiler-rt/lib/sanitizer_common/sanitizer_linux.cc b/projects/compiler-rt/lib/sanitizer_common/sanitizer_linux.cc
index a79a2a155..8c3c1e5d6 100644
--- a/projects/compiler-rt/lib/sanitizer_common/sanitizer_linux.cc
+++ b/projects/compiler-rt/lib/sanitizer_common/sanitizer_linux.cc
@@ -629,8 +629,7 @@ uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5) {
 }
 #endif
 
-uptr internal_sigaltstack(const struct sigaltstack *ss,
-                         struct sigaltstack *oss) {
+uptr internal_sigaltstack(const void *ss, void *oss) {
   return internal_syscall(SYSCALL(sigaltstack), (uptr)ss, (uptr)oss);
 }
 
diff --git a/projects/compiler-rt/lib/sanitizer_common/sanitizer_linux.h b/projects/compiler-rt/lib/sanitizer_common/sanitizer_linux.h
index ee336f7dd..11cad6b80 100644
--- a/projects/compiler-rt/lib/sanitizer_common/sanitizer_linux.h
+++ b/projects/compiler-rt/lib/sanitizer_common/sanitizer_linux.h
@@ -21,7 +21,6 @@
 #include "sanitizer_platform_limits_posix.h"
 
 struct link_map;  // Opaque type returned by dlopen().
-struct sigaltstack;
 
 namespace __sanitizer {
 // Dirent structure for getdents(). Note that this structure is different from
@@ -30,8 +29,7 @@ struct linux_dirent;
 
 // Syscall wrappers.
 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count);
-uptr internal_sigaltstack(const struct sigaltstack* ss,
-                          struct sigaltstack* oss);
+uptr internal_sigaltstack(const void* ss, void* oss);
 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
     __sanitizer_sigset_t *oldset);
 
diff --git a/projects/compiler-rt/lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc b/projects/compiler-rt/lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc
index 03f73ae88..d7fa5f645 100644
--- a/projects/compiler-rt/lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc
+++ b/projects/compiler-rt/lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc
@@ -287,7 +287,7 @@ static int TracerThread(void* argument) {
 
   // Alternate stack for signal handling.
   InternalScopedBuffer<char> handler_stack_memory(kHandlerStackSize);
-  struct sigaltstack handler_stack;
+  stack_t handler_stack;
   internal_memset(&handler_stack, 0, sizeof(handler_stack));
   handler_stack.ss_sp = handler_stack_memory.data();
   handler_stack.ss_size = kHandlerStackSize;
diff --git a/projects/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cc b/projects/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cc
index 0ba01babe..ead1e5704 100644
--- a/projects/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cc
+++ b/projects/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cc
@@ -286,7 +286,7 @@ void InitializePlatform() {
 int ExtractResolvFDs(void *state, int *fds, int nfd) {
 #if SANITIZER_LINUX && !SANITIZER_ANDROID
   int cnt = 0;
-  __res_state *statp = (__res_state*)state;
+  struct __res_state *statp = (struct __res_state*)state;
   for (int i = 0; i < MAXNS && cnt < nfd; i++) {
     if (statp->_u._ext.nsaddrs[i] && statp->_u._ext.nssocks[i] != -1)
       fds[cnt++] = statp->_u._ext.nssocks[i];
diff --git a/projects/compiler-rt/lib/esan/esan_sideline_linux.cpp b/projects/compiler-rt/lib/esan/esan_sideline_linux.cpp
index d04f5909d6a2..bc272dfe49f8 100644
--- a/projects/compiler-rt/lib/esan/esan_sideline_linux.cpp
+++ b/projects/compiler-rt/lib/esan/esan_sideline_linux.cpp
@@ -70,7 +70,7 @@ int SidelineThread::runSideline(void *Arg) {
 
   // Set up a signal handler on an alternate stack for safety.
   InternalScopedBuffer<char> StackMap(SigAltStackSize);
-  struct sigaltstack SigAltStack;
+  stack_t SigAltStack;
   SigAltStack.ss_sp = StackMap.data();
   SigAltStack.ss_size = SigAltStackSize;
   SigAltStack.ss_flags = 0;