Creation of LTS branch "lts_2018_12_18"20181200

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  - 9acad869d21731f5bc50430a33fe61cc0ffcbb0b Merge pull request #150 from OlafvdSpek/patch-2 by Jonathan Cohen <cohenjon@google.com>
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  - 44aa275286baf97fc13529aca547a88b180beb08 Merge pull request #143 from rongjiecomputer/kernel by Xiaoyi Zhang <zhangxy988@gmail.com>
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  - 16ac2ec2e38cdf47f9330a312e319d57da659c10 Merge pull request #134 from rongjiecomputer/cmake by Alex Strelnikov <strel@google.com>
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GitOrigin-RevId: 44b0fafc62d9b8f192e8180cbe9c4b806b339d57
Change-Id: I2c427b5b41b2d34101922048b00f3d9dafcb498d

23 files changed, 88 insertions, 75 deletions

diff --git a/absl/debugging/internal/address_is_readable.cc b/absl/debugging/internal/address_is_readable.cc
index 6282bd6a..2a83f4c8 100644
--- a/absl/debugging/internal/address_is_readable.cc
+++ b/absl/debugging/internal/address_is_readable.cc
@@ -20,14 +20,14 @@
 #if !defined(__linux__) || defined(__ANDROID__)
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 // On platforms other than Linux, just return true.
 bool AddressIsReadable(const void* /* addr */) { return true; }
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #else
@@ -42,7 +42,7 @@ bool AddressIsReadable(const void* /* addr */) { return true; }
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 // Pack a pid and two file descriptors into a 64-bit word,
@@ -131,7 +131,7 @@ bool AddressIsReadable(const void *addr) {
 }
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif
diff --git a/absl/debugging/internal/address_is_readable.h b/absl/debugging/internal/address_is_readable.h
index 7e58ce55..3942f44b 100644
--- a/absl/debugging/internal/address_is_readable.h
+++ b/absl/debugging/internal/address_is_readable.h
@@ -17,7 +17,7 @@
 #define ABSL_DEBUGGING_INTERNAL_ADDRESS_IS_READABLE_H_
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 // Return whether the byte at *addr is readable, without faulting.
@@ -25,7 +25,7 @@ namespace debugging_internal {
 bool AddressIsReadable(const void *addr);
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_ADDRESS_IS_READABLE_H_
diff --git a/absl/debugging/internal/demangle.cc b/absl/debugging/internal/demangle.cc
index 15b7c7c3..57b9393f 100644
--- a/absl/debugging/internal/demangle.cc
+++ b/absl/debugging/internal/demangle.cc
@@ -24,7 +24,7 @@
 #include <limits>
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 typedef struct {
@@ -341,7 +341,7 @@ static bool ZeroOrMore(ParseFunc parse_func, State *state) {
 }
 
 // Append "str" at "out_cur_idx".  If there is an overflow, out_cur_idx is
-// set to out_end_idx+1.  The output std::string is ensured to
+// set to out_end_idx+1.  The output string is ensured to
 // always terminate with '\0' as long as there is no overflow.
 static void Append(State *state, const char *const str, const int length) {
   for (int i = 0; i < length; ++i) {
@@ -841,7 +841,7 @@ static bool ParseNumber(State *state, int *number_out) {
 }
 
 // Floating-point literals are encoded using a fixed-length lowercase
-// hexadecimal std::string.
+// hexadecimal string.
 static bool ParseFloatNumber(State *state) {
   ComplexityGuard guard(state);
   if (guard.IsTooComplex()) return false;
@@ -1637,6 +1637,15 @@ static bool ParseExpression(State *state) {
   }
   state->parse_state = copy;
 
+  // Pointer-to-member access expressions.  This parses the same as a binary
+  // operator, but it's implemented separately because "ds" shouldn't be
+  // accepted in other contexts that parse an operator name.
+  if (ParseTwoCharToken(state, "ds") && ParseExpression(state) &&
+      ParseExpression(state)) {
+    return true;
+  }
+  state->parse_state = copy;
+
   // Parameter pack expansion
   if (ParseTwoCharToken(state, "sp") && ParseExpression(state)) {
     return true;
@@ -1860,5 +1869,5 @@ bool Demangle(const char *mangled, char *out, int out_size) {
 }
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
diff --git a/absl/debugging/internal/demangle.h b/absl/debugging/internal/demangle.h
index 7faa5a2f..1f8722c7 100644
--- a/absl/debugging/internal/demangle.h
+++ b/absl/debugging/internal/demangle.h
@@ -54,7 +54,7 @@
 #define ABSL_DEBUGGING_INTERNAL_DEMANGLE_H_
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 // Demangle `mangled`.  On success, return true and write the
@@ -63,7 +63,7 @@ namespace debugging_internal {
 bool Demangle(const char *mangled, char *out, int out_size);
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_DEMANGLE_H_
diff --git a/absl/debugging/internal/demangle_test.cc b/absl/debugging/internal/demangle_test.cc
index 5ff64a37..fa89fb80 100644
--- a/absl/debugging/internal/demangle_test.cc
+++ b/absl/debugging/internal/demangle_test.cc
@@ -23,7 +23,7 @@
 #include "absl/memory/memory.h"
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 namespace {
 
@@ -189,5 +189,5 @@ TEST(DemangleRegression, DeeplyNestedArrayType) {
 
 }  // namespace
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
diff --git a/absl/debugging/internal/elf_mem_image.cc b/absl/debugging/internal/elf_mem_image.cc
index a2bea919..e7e35e9c 100644
--- a/absl/debugging/internal/elf_mem_image.cc
+++ b/absl/debugging/internal/elf_mem_image.cc
@@ -38,7 +38,7 @@
 #define VERSYM_VERSION 0x7fff
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 namespace {
@@ -376,7 +376,7 @@ void ElfMemImage::SymbolIterator::Update(int increment) {
 }
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_HAVE_ELF_MEM_IMAGE
diff --git a/absl/debugging/internal/elf_mem_image.h b/absl/debugging/internal/elf_mem_image.h
index ea4f5f0c..0adb5f5d 100644
--- a/absl/debugging/internal/elf_mem_image.h
+++ b/absl/debugging/internal/elf_mem_image.h
@@ -39,7 +39,7 @@
 #include <link.h>  // for ElfW
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 // An in-memory ELF image (may not exist on disk).
@@ -124,7 +124,7 @@ class ElfMemImage {
 };
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_HAVE_ELF_MEM_IMAGE
diff --git a/absl/debugging/internal/examine_stack.cc b/absl/debugging/internal/examine_stack.cc
index 1a2b7a42..4764355a 100644
--- a/absl/debugging/internal/examine_stack.cc
+++ b/absl/debugging/internal/examine_stack.cc
@@ -30,7 +30,7 @@
 #include "absl/debugging/symbolize.h"
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 // Returns the program counter from signal context, nullptr if
@@ -53,6 +53,10 @@ void* GetProgramCounter(void* vuc) {
     return reinterpret_cast<void*>(context->uc_mcontext.gp_regs[32]);
 #elif defined(__powerpc__)
     return reinterpret_cast<void*>(context->uc_mcontext.regs->nip);
+#elif defined(__s390__) && !defined(__s390x__)
+    return reinterpret_cast<void*>(context->uc_mcontext.psw.addr & 0x7fffffff);
+#elif defined(__s390__) && defined(__s390x__)
+    return reinterpret_cast<void*>(context->uc_mcontext.psw.addr);
 #elif defined(__x86_64__)
     if (16 < ABSL_ARRAYSIZE(context->uc_mcontext.gregs))
       return reinterpret_cast<void*>(context->uc_mcontext.gregs[16]);
@@ -147,5 +151,5 @@ void DumpPCAndFrameSizesAndStackTrace(
 }
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
diff --git a/absl/debugging/internal/examine_stack.h b/absl/debugging/internal/examine_stack.h
index a51a8b35..474fdd5e 100644
--- a/absl/debugging/internal/examine_stack.h
+++ b/absl/debugging/internal/examine_stack.h
@@ -18,7 +18,7 @@
 #define ABSL_DEBUGGING_INTERNAL_EXAMINE_STACK_H_
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 // Returns the program counter from signal context, or nullptr if
@@ -34,7 +34,7 @@ void DumpPCAndFrameSizesAndStackTrace(
     void (*writerfn)(const char*, void*), void* writerfn_arg);
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_EXAMINE_STACK_H_
diff --git a/absl/debugging/internal/stack_consumption.cc b/absl/debugging/internal/stack_consumption.cc
index 8724007d..94b43e1d 100644
--- a/absl/debugging/internal/stack_consumption.cc
+++ b/absl/debugging/internal/stack_consumption.cc
@@ -27,7 +27,7 @@
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 namespace {
 
@@ -168,7 +168,7 @@ int GetSignalHandlerStackConsumption(void (*signal_handler)(int)) {
 }
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_INTERNAL_HAVE_DEBUGGING_STACK_CONSUMPTION
diff --git a/absl/debugging/internal/stack_consumption.h b/absl/debugging/internal/stack_consumption.h
index 584a4aa9..2defdf0d 100644
--- a/absl/debugging/internal/stack_consumption.h
+++ b/absl/debugging/internal/stack_consumption.h
@@ -27,7 +27,7 @@
 #define ABSL_INTERNAL_HAVE_DEBUGGING_STACK_CONSUMPTION 1
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 // Returns the stack consumption in bytes for the code exercised by
@@ -39,7 +39,7 @@ namespace debugging_internal {
 int GetSignalHandlerStackConsumption(void (*signal_handler)(int));
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_INTERNAL_HAVE_DEBUGGING_STACK_CONSUMPTION
diff --git a/absl/debugging/internal/stack_consumption_test.cc b/absl/debugging/internal/stack_consumption_test.cc
index 4f1351b3..022e508a 100644
--- a/absl/debugging/internal/stack_consumption_test.cc
+++ b/absl/debugging/internal/stack_consumption_test.cc
@@ -23,7 +23,7 @@
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 namespace {
 
@@ -44,7 +44,7 @@ TEST(SignalHandlerStackConsumptionTest, MeasuresStackConsumption) {
 
 }  // namespace
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_INTERNAL_HAVE_DEBUGGING_STACK_CONSUMPTION
diff --git a/absl/debugging/internal/stacktrace_aarch64-inl.inc b/absl/debugging/internal/stacktrace_aarch64-inl.inc
index 0e3fda57..2ed7ae1f 100644
--- a/absl/debugging/internal/stacktrace_aarch64-inl.inc
+++ b/absl/debugging/internal/stacktrace_aarch64-inl.inc
@@ -180,13 +180,13 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return true;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_AARCH64_INL_H_
diff --git a/absl/debugging/internal/stacktrace_arm-inl.inc b/absl/debugging/internal/stacktrace_arm-inl.inc
index ef76782c..eb8ca77c 100644
--- a/absl/debugging/internal/stacktrace_arm-inl.inc
+++ b/absl/debugging/internal/stacktrace_arm-inl.inc
@@ -113,13 +113,13 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return false;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_ARM_INL_H_
diff --git a/absl/debugging/internal/stacktrace_config.h b/absl/debugging/internal/stacktrace_config.h
index 48adfccc..578e4968 100644
--- a/absl/debugging/internal/stacktrace_config.h
+++ b/absl/debugging/internal/stacktrace_config.h
@@ -21,26 +21,16 @@
 #ifndef ABSL_DEBUGGING_INTERNAL_STACKTRACE_CONFIG_H_
 #define ABSL_DEBUGGING_INTERNAL_STACKTRACE_CONFIG_H_
 
-// First, test platforms which only support a stub.
-#if ABSL_STACKTRACE_INL_HEADER
+#if defined(ABSL_STACKTRACE_INL_HEADER)
 #error ABSL_STACKTRACE_INL_HEADER cannot be directly set
-#elif defined(__native_client__) || defined(__APPLE__) || \
-    defined(__FreeBSD__) || defined(__ANDROID__) || defined(__myriad2__) || \
-    defined(__asmjs__) || defined(__wasm__) || defined(__Fuchsia__)
-#define ABSL_STACKTRACE_INL_HEADER \
-    "absl/debugging/internal/stacktrace_unimplemented-inl.inc"
 
-// Next, test for Mips and Windows.
-// TODO(marmstrong): Mips case, remove the check for ABSL_STACKTRACE_INL_HEADER
-#elif defined(__mips__) && !defined(ABSL_STACKTRACE_INL_HEADER)
-#define ABSL_STACKTRACE_INL_HEADER \
-    "absl/debugging/internal/stacktrace_unimplemented-inl.inc"
-#elif defined(_WIN32)  // windows
+#elif defined(_WIN32)
 #define ABSL_STACKTRACE_INL_HEADER \
     "absl/debugging/internal/stacktrace_win32-inl.inc"
 
-// Finally, test NO_FRAME_POINTER.
-#elif !defined(NO_FRAME_POINTER)
+#elif defined(__linux__) && !defined(__ANDROID__)
+
+#if !defined(NO_FRAME_POINTER)
 # if defined(__i386__) || defined(__x86_64__)
 #define ABSL_STACKTRACE_INL_HEADER \
     "absl/debugging/internal/stacktrace_x86-inl.inc"
@@ -51,24 +41,30 @@
 #define ABSL_STACKTRACE_INL_HEADER \
     "absl/debugging/internal/stacktrace_aarch64-inl.inc"
 # elif defined(__arm__)
+// Note: When using glibc this may require -funwind-tables to function properly.
 #define ABSL_STACKTRACE_INL_HEADER \
-    "absl/debugging/internal/stacktrace_arm-inl.inc"
+  "absl/debugging/internal/stacktrace_generic-inl.inc"
+# else
+#define ABSL_STACKTRACE_INL_HEADER \
+   "absl/debugging/internal/stacktrace_unimplemented-inl.inc"
 # endif
 #else  // defined(NO_FRAME_POINTER)
 # if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__)
 #define ABSL_STACKTRACE_INL_HEADER \
-    "absl/debugging/internal/stacktrace_unimplemented-inl.inc"
+    "absl/debugging/internal/stacktrace_generic-inl.inc"
 # elif defined(__ppc__) || defined(__PPC__)
-//  Use glibc's backtrace.
 #define ABSL_STACKTRACE_INL_HEADER \
     "absl/debugging/internal/stacktrace_generic-inl.inc"
-# elif defined(__arm__)
-#   error stacktrace without frame pointer is not supported on ARM
+# else
+#define ABSL_STACKTRACE_INL_HEADER \
+   "absl/debugging/internal/stacktrace_unimplemented-inl.inc"
 # endif
 #endif  // NO_FRAME_POINTER
 
-#if !defined(ABSL_STACKTRACE_INL_HEADER)
-#error Not supported yet
+#else
+#define ABSL_STACKTRACE_INL_HEADER \
+  "absl/debugging/internal/stacktrace_unimplemented-inl.inc"
+
 #endif
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_CONFIG_H_
diff --git a/absl/debugging/internal/stacktrace_generic-inl.inc b/absl/debugging/internal/stacktrace_generic-inl.inc
index 5d7492a4..823942af 100644
--- a/absl/debugging/internal/stacktrace_generic-inl.inc
+++ b/absl/debugging/internal/stacktrace_generic-inl.inc
@@ -19,6 +19,7 @@
 template <bool IS_STACK_FRAMES, bool IS_WITH_CONTEXT>
 static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
                       const void *ucp, int *min_dropped_frames) {
+  static_cast<void>(ucp);  // Unused.
   static const int kStackLength = 64;
   void * stack[kStackLength];
   int size;
@@ -49,13 +50,13 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return true;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_GENERIC_INL_H_
diff --git a/absl/debugging/internal/stacktrace_powerpc-inl.inc b/absl/debugging/internal/stacktrace_powerpc-inl.inc
index 86ac8534..aff2d516 100644
--- a/absl/debugging/internal/stacktrace_powerpc-inl.inc
+++ b/absl/debugging/internal/stacktrace_powerpc-inl.inc
@@ -31,6 +31,8 @@
 #include <cstdint>
 #include <cstdio>
 
+#include "absl/base/attributes.h"
+#include "absl/base/optimization.h"
 #include "absl/base/port.h"
 #include "absl/debugging/stacktrace.h"
 #include "absl/debugging/internal/address_is_readable.h"
@@ -150,8 +152,9 @@ static void **NextStackFrame(void **old_sp, const void *uc) {
 }
 
 // This ensures that absl::GetStackTrace sets up the Link Register properly.
-void StacktracePowerPCDummyFunction() __attribute__((noinline));
-void StacktracePowerPCDummyFunction() { __asm__ volatile(""); }
+ABSL_ATTRIBUTE_NOINLINE static void AbslStacktracePowerPCDummyFunction() {
+  ABSL_BLOCK_TAIL_CALL_OPTIMIZATION();
+}
 
 template <bool IS_STACK_FRAMES, bool IS_WITH_CONTEXT>
 ABSL_ATTRIBUTE_NO_SANITIZE_ADDRESS  // May read random elements from stack.
@@ -176,7 +179,7 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
   // want here.  While the compiler will always(?) set up LR for
   // subroutine calls, it may not for leaf functions (such as this one).
   // This routine forces the compiler (at least gcc) to push it anyway.
-  StacktracePowerPCDummyFunction();
+  AbslStacktracePowerPCDummyFunction();
 
   // The LR save area is used by the callee, so the top entry is bogus.
   skip_count++;
@@ -233,13 +236,13 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return true;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_POWERPC_INL_H_
diff --git a/absl/debugging/internal/stacktrace_unimplemented-inl.inc b/absl/debugging/internal/stacktrace_unimplemented-inl.inc
index 8c3ed4d7..65345efc 100644
--- a/absl/debugging/internal/stacktrace_unimplemented-inl.inc
+++ b/absl/debugging/internal/stacktrace_unimplemented-inl.inc
@@ -12,13 +12,13 @@ static int UnwindImpl(void** /* result */, int* /* sizes */,
 }
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return false;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_UNIMPLEMENTED_INL_H_
diff --git a/absl/debugging/internal/stacktrace_win32-inl.inc b/absl/debugging/internal/stacktrace_win32-inl.inc
index ceca299d..59e72785 100644
--- a/absl/debugging/internal/stacktrace_win32-inl.inc
+++ b/absl/debugging/internal/stacktrace_win32-inl.inc
@@ -73,13 +73,13 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return false;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_WIN32_INL_H_
diff --git a/absl/debugging/internal/stacktrace_x86-inl.inc b/absl/debugging/internal/stacktrace_x86-inl.inc
index 13afce7b..d29cd84b 100644
--- a/absl/debugging/internal/stacktrace_x86-inl.inc
+++ b/absl/debugging/internal/stacktrace_x86-inl.inc
@@ -327,13 +327,13 @@ static int UnwindImpl(void **result, int *sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return true;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_X86_INL_INC_
diff --git a/absl/debugging/internal/symbolize.h b/absl/debugging/internal/symbolize.h
index fd10a637..2791105e 100644
--- a/absl/debugging/internal/symbolize.h
+++ b/absl/debugging/internal/symbolize.h
@@ -34,7 +34,7 @@
 #include <string>
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 // Iterates over all sections, invoking callback on each with the section name
@@ -53,13 +53,13 @@ bool GetSectionHeaderByName(int fd, const char *name, size_t name_len,
                             ElfW(Shdr) *out);
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 struct SymbolDecoratorArgs {
@@ -121,7 +121,7 @@ bool GetFileMappingHint(const void** start,
                         const char** filename);
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_SYMBOLIZE_H_
diff --git a/absl/debugging/internal/vdso_support.cc b/absl/debugging/internal/vdso_support.cc
index fd1fb05e..85b52bc8 100644
--- a/absl/debugging/internal/vdso_support.cc
+++ b/absl/debugging/internal/vdso_support.cc
@@ -38,7 +38,7 @@
 #endif
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 ABSL_CONST_INIT
@@ -188,7 +188,7 @@ static class VDSOInitHelper {
 } vdso_init_helper;
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_HAVE_VDSO_SUPPORT
diff --git a/absl/debugging/internal/vdso_support.h b/absl/debugging/internal/vdso_support.h
index 7fdd7527..035e5964 100644
--- a/absl/debugging/internal/vdso_support.h
+++ b/absl/debugging/internal/vdso_support.h
@@ -53,7 +53,7 @@
 #endif
 
 namespace absl {
-inline namespace lts_2018_06_20 {
+inline namespace lts_2018_12_18 {
 namespace debugging_internal {
 
 // NOTE: this class may be used from within tcmalloc, and can not
@@ -150,7 +150,7 @@ class VDSOSupport {
 int GetCPU();
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2018_06_20
+}  // inline namespace lts_2018_12_18
 }  // namespace absl
 
 #endif  // ABSL_HAVE_ELF_MEM_IMAGE