[compiler-rt] r349402 - Don't trigger sanitizer initialization from `sysctlbyname` and `sysctl` interceptor.

[Dan Liew via llvm-commits]

Author: delcypher
Date: Mon Dec 17 13:42:55 2018
New Revision: 349402

URL: http://llvm.org/viewvc/llvm-project?rev=349402&view=rev
Log:
Don't trigger sanitizer initialization from `sysctlbyname`  and `sysctl` interceptor.

Summary:
This fixes the `ThreadSanitizer-x86_64-iossim` testsuite which broke
when r348770 (https://reviews.llvm.org/D55473) landed.

The root cause of the problem is that early-on during the iOS simulator
init process a call to `sysctlbyname` is issued. If the TSan initializer
is triggered at this point it will eventually trigger a call to
`__cxa_at_exit(...)`. This call then aborts because the library
implementing this function is not yet had its initialization function
called.

rdar://problem/46696934

Reviewers: kubamracek, george.karpenkov, devnexen, vitalybuka, krytarowski

Subscribers: #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D55711

Modified:
    compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc

Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc?rev=349402&r1=349401&r2=349402&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc Mon Dec 17 13:42:55 2018
@@ -7539,6 +7539,8 @@ INTERCEPTOR(int, fts_close, void *ftsp)
 INTERCEPTOR(int, sysctl, int *name, unsigned int namelen, void *oldp,
             SIZE_T *oldlenp, void *newp, SIZE_T newlen) {
   void *ctx;
+  if (COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED)
+    return internal_sysctl(name, namelen, oldp, oldlenp, newp, newlen);
   COMMON_INTERCEPTOR_ENTER(ctx, sysctl, name, namelen, oldp, oldlenp, newp,
                            newlen);
   if (name)
@@ -7561,6 +7563,8 @@ INTERCEPTOR(int, sysctl, int *name, unsi
 INTERCEPTOR(int, sysctlbyname, char *sname, void *oldp, SIZE_T *oldlenp,
             void *newp, SIZE_T newlen) {
   void *ctx;
+  if (COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED)
+    return internal_sysctlbyname(sname, oldp, oldlenp, newp, newlen);
   COMMON_INTERCEPTOR_ENTER(ctx, sysctlbyname, sname, oldp, oldlenp, newp,
                            newlen);
   if (sname)