Add vendored dependencies & cleanup script

third_party/abseil-cpp/patches/0001-Turn-on-hardened-mode.patch

@@ -0,0 +1,24 @@
+From a2df3397d72987acaf6687a55e5ed58cd68b0158 Mon Sep 17 00:00:00 2001
+From: Mirko Bonadei <mbonadei@chromium.org>
+Date: Fri, 17 Apr 2020 14:21:07 +0200
+Subject: [PATCH] Turn on hardened mode.
+
+---
+ third_party/abseil-cpp/absl/base/options.h | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/third_party/abseil-cpp/absl/base/options.h b/third_party/abseil-cpp/absl/base/options.h
+index 230bf1eecc4a..df506f0fae64 100644
+--- a/third_party/abseil-cpp/absl/base/options.h
++++ b/third_party/abseil-cpp/absl/base/options.h
+@@ -233,6 +233,6 @@
+ // checks enabled by this option may abort the program in a different way and
+ // log additional information when `NDEBUG` is not defined.
+ 
+-#define ABSL_OPTION_HARDENED 0
++#define ABSL_OPTION_HARDENED 1
+ 
+ #endif  // ABSL_BASE_OPTIONS_H_
+-- 
+2.26.0.110.g2183baf09c-goog
+

third_party/abseil-cpp/patches/0002-delete-unprefixed-annotations.patch

@@ -0,0 +1,27 @@
+diff --git a/third_party/abseil-cpp/absl/base/dynamic_annotations.h b/third_party/abseil-cpp/absl/base/dynamic_annotations.h
+index 1444dc48e283..6687291cade3 100644
+--- a/third_party/abseil-cpp/absl/base/dynamic_annotations.h
++++ b/third_party/abseil-cpp/absl/base/dynamic_annotations.h
+@@ -49,9 +49,6 @@
+ 
+ #include "absl/base/config.h"
+ 
+-// TODO(rogeeff): Remove after the backward compatibility period.
+-#include "absl/base/internal/dynamic_annotations.h"  // IWYU pragma: export
+-
+ // -------------------------------------------------------------------------
+ // Decide which features are enabled
+ 
+diff --git a/third_party/abseil-cpp/absl/base/thread_annotations.h b/third_party/abseil-cpp/absl/base/thread_annotations.h
+index 5f51c0c2d2d5..10b9bde551a7 100644
+--- a/third_party/abseil-cpp/absl/base/thread_annotations.h
++++ b/third_party/abseil-cpp/absl/base/thread_annotations.h
+@@ -35,8 +35,6 @@
+ #define ABSL_BASE_THREAD_ANNOTATIONS_H_
+ 
+ #include "absl/base/config.h"
+-// TODO(mbonadei): Remove after the backward compatibility period.
+-#include "absl/base/internal/thread_annotations.h"  // IWYU pragma: export
+ 
+ #if defined(__clang__)
+ #define ABSL_INTERNAL_THREAD_ANNOTATION_ATTRIBUTE(x) __attribute__((x))

third_party/abseil-cpp/patches/0003-delete-static-initializer-in-stacktrace.patch

@@ -0,0 +1,31 @@
+diff --git a/third_party/abseil-cpp/absl/debugging/internal/stacktrace_generic-inl.inc b/third_party/abseil-cpp/absl/debugging/internal/stacktrace_generic-inl.inc
+index b2792a1f3ada..b94c61233ba3 100644
+--- a/third_party/abseil-cpp/absl/debugging/internal/stacktrace_generic-inl.inc
++++ b/third_party/abseil-cpp/absl/debugging/internal/stacktrace_generic-inl.inc
+@@ -43,17 +43,6 @@ static __thread int recursive = 0;
+ // glibc implementation itself will trigger malloc the first time it is called.
+ // As such, we suppress usage of backtrace during this early stage of execution.
+ static std::atomic<bool> disable_stacktraces(true);  // Disabled until healthy.
+-// Waiting until static initializers run seems to be late enough.
+-// This file is included into stacktrace.cc so this will only run once.
+-ABSL_ATTRIBUTE_UNUSED static int stacktraces_enabler = []() {
+-  void* unused_stack[1];
+-  // Force the first backtrace to happen early to get the one-time shared lib
+-  // loading (allocation) out of the way. After the first call it is much safer
+-  // to use backtrace from a signal handler if we crash somewhere later.
+-  backtrace(unused_stack, 1);
+-  disable_stacktraces.store(false, std::memory_order_relaxed);
+-  return 0;
+-}();
+ 
+ template <bool IS_STACK_FRAMES, bool IS_WITH_CONTEXT>
+ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
+@@ -99,7 +88,7 @@ namespace absl {
+ ABSL_NAMESPACE_BEGIN
+ namespace debugging_internal {
+ bool StackTraceWorksForTest() {
+-  return true;
++  return false;
+ }
+ }  // namespace debugging_internal
+ ABSL_NAMESPACE_END