vendor/llvm-project/llvmorg-11-init-20887-g2e10b7a39b9vendor/llvm-project/master

1 files changed, 15 insertions, 3 deletions

diff --git a/compiler-rt/lib/gwp_asan/options.inc b/compiler-rt/lib/gwp_asan/options.inc
index df6c46e6e98f..6cdddfbad84d 100644
--- a/compiler-rt/lib/gwp_asan/options.inc
+++ b/compiler-rt/lib/gwp_asan/options.inc
@@ -17,9 +17,10 @@ GWP_ASAN_OPTION(
     "When allocations are right-aligned, should we perfectly align them up to "
     "the page boundary? By default (false), we round up allocation size to the "
     "nearest power of two (1, 2, 4, 8, 16) up to a maximum of 16-byte "
-    "alignment for performance reasons. Setting this to true can find single "
-    "byte buffer-overflows for multibyte allocations at the cost of "
-    "performance, and may be incompatible with some architectures.")
+    "alignment for performance reasons. For Bionic, we use 8-byte alignment by "
+    "default. Setting this to true can find single byte buffer-overflows for "
+    "multibyte allocations at the cost of performance, and may be incompatible "
+    "with some architectures.")
 
 GWP_ASAN_OPTION(int, MaxSimultaneousAllocations, 16,
                 "Number of simultaneously-guarded allocations available in the "
@@ -30,6 +31,13 @@ GWP_ASAN_OPTION(int, SampleRate, 5000,
                 "selected for GWP-ASan sampling. Default is 5000. Sample rates "
                 "up to (2^31 - 1) are supported.")
 
+// Developer note - This option is not actually processed by GWP-ASan itself. It
+// is included here so that a user can specify whether they want signal handlers
+// or not. The supporting allocator should inspect this value to see whether
+// signal handlers need to be installed, and then use
+// crash_handler::installSignalHandlers() in order to install the handlers. Note
+// that in order to support signal handlers, you will need to link against the
+// optional crash_handler component.
 GWP_ASAN_OPTION(
     bool, InstallSignalHandlers, true,
     "Install GWP-ASan signal handlers for SIGSEGV during dynamic loading. This "
@@ -39,3 +47,7 @@ GWP_ASAN_OPTION(
     "programs that install further signal handlers should make sure they do "
     "the same. Note, if the previously installed SIGSEGV handler is SIG_IGN, "
     "we terminate the process after dumping the error report.")
+
+GWP_ASAN_OPTION(bool, InstallForkHandlers, true,
+                "Install GWP-ASan atfork handlers to acquire internal locks "
+                "before fork and release them after.")