[compiler-rt] 12f27fc - [Darwin] Cleanup code via improved GetMacosAlignedVersion()

[Julian Lettner via llvm-commits]

Author: Julian Lettner
Date: 2020-07-28T09:48:34-07:00
New Revision: 12f27fc4b505da848a06b37488c5717bf9e3b85d

URL: https://github.com/llvm/llvm-project/commit/12f27fc4b505da848a06b37488c5717bf9e3b85d
DIFF: https://github.com/llvm/llvm-project/commit/12f27fc4b505da848a06b37488c5717bf9e3b85d.diff

LOG: [Darwin] Cleanup code via improved GetMacosAlignedVersion()

Checking the OS version via `GetMacosAlignedVersion()` now works in
simulators [1].  Let's use it to simplify `DyldNeedsEnvVariable()`.

[1] 3fb0de820796cc6e322c8378713d375d9870a353

Reviewed By: delcypher

Differential Revision: https://reviews.llvm.org/D81197

Added: 
    

Modified: 
    compiler-rt/lib/sanitizer_common/sanitizer_mac.cpp
    compiler-rt/lib/sanitizer_common/sanitizer_mac.h

Removed: 
    


################################################################################
diff  --git a/compiler-rt/lib/sanitizer_common/sanitizer_mac.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_mac.cpp
index 522a909e9528..f96f18713197 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_mac.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_mac.cpp
@@ -879,20 +879,10 @@ bool ReexecDisabled() {
   return false;
 }
 
-extern "C" SANITIZER_WEAK_ATTRIBUTE double dyldVersionNumber;
-static const double kMinDyldVersionWithAutoInterposition = 360.0;
-
-bool DyldNeedsEnvVariable() {
-  // Although sanitizer support was added to LLVM on OS X 10.7+, GCC users
-  // still may want use them on older systems. On older Darwin platforms, dyld
-  // doesn't export dyldVersionNumber symbol and we simply return true.
-  if (!&dyldVersionNumber) return true;
+static bool DyldNeedsEnvVariable() {
   // If running on OS X 10.11+ or iOS 9.0+, dyld will interpose even if
-  // DYLD_INSERT_LIBRARIES is not set. However, checking OS version via
-  // GetMacosAlignedVersion() doesn't work for the simulator. Let's instead
-  // check `dyldVersionNumber`, which is exported by dyld, against a known
-  // version number from the first OS release where this appeared.
-  return dyldVersionNumber < kMinDyldVersionWithAutoInterposition;
+  // DYLD_INSERT_LIBRARIES is not set.
+  return GetMacosAlignedVersion() < MacosVersion(10, 11);
 }
 
 void MaybeReexec() {

diff  --git a/compiler-rt/lib/sanitizer_common/sanitizer_mac.h b/compiler-rt/lib/sanitizer_common/sanitizer_mac.h
index 90ecff4815c2..f61ebe2566e5 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_mac.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_mac.h
@@ -44,6 +44,7 @@ struct VersionBase {
     return major > other.major ||
            (major == other.major && minor >= other.minor);
   }
+  bool operator<(const VersionType &other) const { return !(*this >= other); }
 };
 
 struct MacosVersion : VersionBase<MacosVersion> {