Explicitly specify whether to emit frame pointers by default.

base/debug/stack_trace.h

Index: base/debug/stack_trace.h
diff --git a/base/debug/stack_trace.h b/base/debug/stack_trace.h
index ab1d2ebe6a3c00244b5d09cb1e4fcadce16ab093..e98ffecbe081516652c7354ea8ac85e60a7f4889 100644
--- a/base/debug/stack_trace.h
+++ b/base/debug/stack_trace.h
@@ -23,23 +23,14 @@ struct _EXCEPTION_POINTERS;
 struct _CONTEXT;
 #endif
 
-// TODO(699863): Clean up HAVE_TRACE_STACK_FRAME_POINTERS.
-#if defined(OS_POSIX)
-
-#if defined(__i386__) || defined(__x86_64__)
-#define HAVE_TRACE_STACK_FRAME_POINTERS 1
-#elif defined(__arm__) && !defined(__thumb__)
-#define HAVE_TRACE_STACK_FRAME_POINTERS 1
-#else  // defined(__arm__) && !defined(__thumb__)
-#define HAVE_TRACE_STACK_FRAME_POINTERS 0
-#endif  // defined(__arm__) && !defined(__thumb__)
-
-#elif defined(OS_WIN)
-#define HAVE_TRACE_STACK_FRAME_POINTERS 1
-
-#else  // defined(OS_WIN)
-#define HAVE_TRACE_STACK_FRAME_POINTERS 0
-#endif  // defined(OS_WIN)
+// Unwinding using frame pointers requires stack traces to have frame pointers
+// by default. This still doesn't work on thumb architectures, due to an llvm
+// bug. https://bugs.llvm.org/show_bug.cgi?id=18505#c5
+#if ENABLED_FRAME_POINTERS && !(defined(__arm__) && defined(__thumb__))

[Mark Mentovai, 2017/03/30 23:43:29]

Don’t you need to #include something to get ENABLED_FRAME_POINTERS set properly?

[erikchen, 2017/04/03 06:33:39]

yup

+#define CAN_UNWIND_WITH_FRAME_POINTERS 1
+#else
+#define CAN_UNWIND_WITH_FRAME_POINTERS 0
+#endif
 
 namespace base {
 namespace debug {
@@ -56,7 +47,7 @@ namespace debug {
 BASE_EXPORT bool EnableInProcessStackDumping();
 
 // Returns end of the stack, or 0 if we couldn't get it.
-#if HAVE_TRACE_STACK_FRAME_POINTERS
+#if CAN_UNWIND_WITH_FRAME_POINTERS
 BASE_EXPORT uintptr_t GetStackEnd();
 #endif
 
@@ -119,7 +110,7 @@ class BASE_EXPORT StackTrace {
   size_t count_;
 };
 
-#if HAVE_TRACE_STACK_FRAME_POINTERS
+#if CAN_UNWIND_WITH_FRAME_POINTERS
 // Traces the stack by using frame pointers. This function is faster but less
 // reliable than StackTrace. It should work for debug and profiling builds,
 // but not for release builds (although there are some exceptions).
@@ -184,7 +175,7 @@ class BASE_EXPORT ScopedStackFrameLinker {
 };
 #endif  // !defined(OS_WIN)
 
-#endif  // HAVE_TRACE_STACK_FRAME_POINTERS
+#endif  // CAN_UNWIND_WITH_FRAME_POINTERS
 
 namespace internal {