Creation of LTS branch "lts_2020_02_25"20200225

  - 0033c9ea91a52ade7c6b725aa2ef3cbe15463421 Fix build on FreeBSD/powerpc (#616) by kgotlinux <60880393+kgotlinux@users.noreply.github.com>
  - 0d5ce2797eb695aee7e019e25323251ef6ffc277 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
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  - 2a5633fc077a58528cdbfe78720f3f6bfdc6044d Merge "Export of internal Abseil changes" by Xiaoyi Zhang <zhangxy@google.com>
  - f9b3d6e493c1b6ab3dbdab71c5f8fa849db4abaf Add RISCV support to GetProgramCounter() (#621) by Khem Raj <raj.khem@gmail.com>
  - 0232c87f21c26718aa3eb2d86678070f3b498a4e Add missing ABSL_HAVE_VDSO_SUPPORT conditional (#622) by Sinan Kaya <41809318+franksinankaya@users.noreply.github.com>
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  - 36bcd9599b3f48c99357ba61cf33584889306d6a Fix pointer format specifier in documentation (#614) by Andre Nguyen <andre-nguyen@users.noreply.github.com>
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  - 44427702614d7b86b064ba06a390f5eb2f85dbf6 fix: Add support for more ARM processors detection (#608) by Andre Nguyen <andre-nguyen@users.noreply.github.com>
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  - a2e6adecc294dc4cd98cc285a9134ce58e0f2ad0 Use https links. (#586) by nlewycky <nicholas@mxc.ca>
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  - 85092b4b648ca729c6263c4a302a41dfff28705e Fix Conan builds (#400) by Adrian Ostrowski <adr.ostrowski@gmail.com>
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  - 078b89b3c046d230ef3ad39494e5852184eb528b Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 19b021cb3ff23048dfbe236a4e611925d8930831 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - ecc0033b54847f6c9ee37dbb0be8aa17e5b6d37b Always enable proper symbolize implementation on Windows ... by Loo Rong Jie <loorongjie@gmail.com>
  - 2796d500aea5a31d26b8b24a33fab7a1c8fa2f32 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
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  - a15364ce4d88534ae2295127e5d8e32aefb6b446 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - ab3552a18964e7063c8324f45b3896a6a20b08a8 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - e9f9000c7c80993cb589d011616b7a8016e42f4a Fix ABSL_WAITER_MODE detection for mingw (#342) by Joe Sylve <Joe.Sylve@gmail.com>
  - abea769b551f7a100f540967cb95debdb0080df8 Fix ABSL_HAVE_ALARM check on mingw (#341) by Joe Sylve <Joe.Sylve@gmail.com>
  - 25597bdfc148e91e27678ec30efa52f4fc8c164f Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - aad33fefaa8f744d71ce747a53717b835bdf8e84 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 8fe7214fe2d7a45ecc4d85f6a524c6b1532426de Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - debac94cfb5a0fa75d1d97c399682bd1c72e3191 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 882b3501a31eb0e4ae4213afb91a0e43feda7d5f Fix spelling errors (#384) by Sungmann Cho <55860394+chosungmann@users.noreply.github.com>
  - 502efe6d7841bff82b1aeef5500491fe9a48c635 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - ccdd1d57b6386ebc26fb0c7d99b604672437c124 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - ddf8e52a2918dd0ccec75d3e2426125fa3926724 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 6ec136281086b71da32b5fb068bd6e46b78a5c79 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - ac78ffc3bc0a8b295cab9a03817760fd460df2a1 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 5374c56e5196320681993869e3126b51edac2a43 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 97c1664b4bbab5f78fac2b151ab02656268fb34b Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 325fd7b042ff4ec34f7dd32e602cd81ad0e24b22 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 83c1d65c90a92aa49632b9ac5a793214bb0768bc Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - eb6b7bd23bc0815bfd784e1a74021ce166765280 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 9ddac555b7861dc178d0dbe758a1cfbed718784b Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 1948f6f967e34db9793cfa8b4bcbaf370d039fd8 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - a0d1e098c2f99694fa399b175a7ccf920762030e Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 2d2d7fbc283315b676159716376e739d3d23ed94 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 0302d1e5fa4fcdd1763b7d1bb3212943b1ae911d supppress unused variable warning for gcc (#372) by Martin <pizzard@users.noreply.github.com>
  - 262d74ba81b1fc4d71f459555cde8ecb39786d68 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - f0afae0d49af3e15a7169e019634d7719143d94d Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 0e7afdcbd24c7e5b7cab4e0217d8886f1525b520 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 9a41ffdd3a0ccbcdd29c4e3886b28e06f2cd9c66 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 36910d3d7e9fccadd6603f232d0c4f54dcd47c7e [bazel] Add fixes for --incompatible_load_cc_rules_from_b... by Yannic <contact@yannic-bonenberger.com>
  - aae8143cf9aa611f70d7ea9b95b8b8b383b2271a Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - d9aa92d7fb324314f9df487ac23d32a25650b742 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 321ab5303023c86cd15d9ddc5740fb4b4fde32e1 Export of internal Abseil changes by Abseil Team <absl-team@google.com>
  - 4ef574064e75b86f115549e9eb4c7e806781b3ab Export of internal Abseil changes by Abseil Team <absl-team@google.com>

GitOrigin-RevId: 0033c9ea91a52ade7c6b725aa2ef3cbe15463421
Change-Id: I8a2b70063cb3ab40c6943a6db0fe40cae71ed8d7

22 files changed, 113 insertions, 65 deletions

diff --git a/absl/debugging/internal/address_is_readable.cc b/absl/debugging/internal/address_is_readable.cc
index 64dd285b..65376063 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_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // On platforms other than Linux, just return true.
 bool AddressIsReadable(const void* /* addr */) { return true; }
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #else
@@ -35,14 +35,16 @@ bool AddressIsReadable(const void* /* addr */) { return true; }
 #include <fcntl.h>
 #include <sys/syscall.h>
 #include <unistd.h>
+
 #include <atomic>
 #include <cerrno>
 #include <cstdint>
 
+#include "absl/base/internal/errno_saver.h"
 #include "absl/base/internal/raw_logging.h"
 
 namespace absl {
-inline namespace lts_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Pack a pid and two file descriptors into a 64-bit word,
@@ -67,7 +69,7 @@ static void Unpack(uint64_t x, int *pid, int *read_fd, int *write_fd) {
 // This is a namespace-scoped variable for correct zero-initialization.
 static std::atomic<uint64_t> pid_and_fds;  // initially 0, an invalid pid.
 bool AddressIsReadable(const void *addr) {
-  int save_errno = errno;
+  absl::base_internal::ErrnoSaver errno_saver;
   // We test whether a byte is readable by using write().  Normally, this would
   // be done via a cached file descriptor to /dev/null, but linux fails to
   // check whether the byte is readable when the destination is /dev/null, so
@@ -126,12 +128,11 @@ bool AddressIsReadable(const void *addr) {
                                           std::memory_order_relaxed);
     }
   } while (errno == EBADF);
-  errno = save_errno;
   return bytes_written == 1;
 }
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif
diff --git a/absl/debugging/internal/address_is_readable.h b/absl/debugging/internal/address_is_readable.h
index dc626e5b..4bbaf4d6 100644
--- a/absl/debugging/internal/address_is_readable.h
+++ b/absl/debugging/internal/address_is_readable.h
@@ -15,8 +15,10 @@
 #ifndef ABSL_DEBUGGING_INTERNAL_ADDRESS_IS_READABLE_H_
 #define ABSL_DEBUGGING_INTERNAL_ADDRESS_IS_READABLE_H_
 
+#include "absl/base/config.h"
+
 namespace absl {
-inline namespace lts_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Return whether the byte at *addr is readable, without faulting.
@@ -24,7 +26,7 @@ namespace debugging_internal {
 bool AddressIsReadable(const void *addr);
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 976e47a6..fc615c3f 100644
--- a/absl/debugging/internal/demangle.cc
+++ b/absl/debugging/internal/demangle.cc
@@ -24,7 +24,7 @@
 #include <limits>
 
 namespace absl {
-inline namespace lts_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 typedef struct {
@@ -94,6 +94,8 @@ static const AbbrevPair kOperatorList[] = {
 };
 
 // List of builtin types from Itanium C++ ABI.
+//
+// Invariant: only one- or two-character type abbreviations here.
 static const AbbrevPair kBuiltinTypeList[] = {
     {"v", "void", 0},
     {"w", "wchar_t", 0},
@@ -116,6 +118,16 @@ static const AbbrevPair kBuiltinTypeList[] = {
     {"e", "long double", 0},
     {"g", "__float128", 0},
     {"z", "ellipsis", 0},
+
+    {"De", "decimal128", 0},      // IEEE 754r decimal floating point (128 bits)
+    {"Dd", "decimal64", 0},       // IEEE 754r decimal floating point (64 bits)
+    {"Dc", "decltype(auto)", 0},
+    {"Da", "auto", 0},
+    {"Dn", "std::nullptr_t", 0},  // i.e., decltype(nullptr)
+    {"Df", "decimal32", 0},       // IEEE 754r decimal floating point (32 bits)
+    {"Di", "char32_t", 0},
+    {"Ds", "char16_t", 0},
+    {"Dh", "float16", 0},         // IEEE 754r half-precision float (16 bits)
     {nullptr, nullptr, 0},
 };
 
@@ -1169,12 +1181,6 @@ static bool ParseType(State *state) {
   }
   state->parse_state = copy;
 
-  // nullptr_t, i.e. decltype(nullptr).
-  if (ParseTwoCharToken(state, "Dn")) {
-    return true;
-  }
-  state->parse_state = copy;
-
   if (ParseOneCharToken(state, 'U') && ParseSourceName(state) &&
       ParseType(state)) {
     return true;
@@ -1215,16 +1221,26 @@ static bool ParseCVQualifiers(State *state) {
   return num_cv_qualifiers > 0;
 }
 
-// <builtin-type> ::= v, etc.
+// <builtin-type> ::= v, etc.  # single-character builtin types
 //                ::= u <source-name>
+//                ::= Dd, etc.  # two-character builtin types
+//
+// Not supported:
+//                ::= DF <number> _ # _FloatN (N bits)
+//
 static bool ParseBuiltinType(State *state) {
   ComplexityGuard guard(state);
   if (guard.IsTooComplex()) return false;
   const AbbrevPair *p;
   for (p = kBuiltinTypeList; p->abbrev != nullptr; ++p) {
-    if (RemainingInput(state)[0] == p->abbrev[0]) {
+    // Guaranteed only 1- or 2-character strings in kBuiltinTypeList.
+    if (p->abbrev[1] == '\0') {
+      if (ParseOneCharToken(state, p->abbrev[0])) {
+        MaybeAppend(state, p->real_name);
+        return true;
+      }
+    } else if (p->abbrev[2] == '\0' && ParseTwoCharToken(state, p->abbrev)) {
       MaybeAppend(state, p->real_name);
-      ++state->parse_state.mangled_idx;
       return true;
     }
   }
@@ -1875,5 +1891,5 @@ bool Demangle(const char *mangled, char *out, int out_size) {
 }
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/debugging/internal/demangle.h b/absl/debugging/internal/demangle.h
index 20adbe9c..c314d9bc 100644
--- a/absl/debugging/internal/demangle.h
+++ b/absl/debugging/internal/demangle.h
@@ -53,8 +53,10 @@
 #ifndef ABSL_DEBUGGING_INTERNAL_DEMANGLE_H_
 #define ABSL_DEBUGGING_INTERNAL_DEMANGLE_H_
 
+#include "absl/base/config.h"
+
 namespace absl {
-inline namespace lts_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Demangle `mangled`.  On success, return true and write the
@@ -63,7 +65,7 @@ namespace debugging_internal {
 bool Demangle(const char *mangled, char *out, int out_size);
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 7c50fe3a..c6f1ce18 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_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 namespace {
 
@@ -191,5 +191,5 @@ TEST(DemangleRegression, DeeplyNestedArrayType) {
 
 }  // namespace
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/debugging/internal/elf_mem_image.cc b/absl/debugging/internal/elf_mem_image.cc
index a795117a..24cc0130 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_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 namespace {
@@ -376,7 +376,7 @@ void ElfMemImage::SymbolIterator::Update(int increment) {
 }
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 fcd32afe..46bfade3 100644
--- a/absl/debugging/internal/elf_mem_image.h
+++ b/absl/debugging/internal/elf_mem_image.h
@@ -23,6 +23,8 @@
 // used.
 #include <climits>
 
+#include "absl/base/config.h"
+
 // Maybe one day we can rewrite this file not to require the elf
 // symbol extensions in glibc, but for right now we need them.
 #ifdef ABSL_HAVE_ELF_MEM_IMAGE
@@ -39,7 +41,7 @@
 #include <link.h>  // for ElfW
 
 namespace absl {
-inline namespace lts_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // An in-memory ELF image (may not exist on disk).
@@ -124,7 +126,7 @@ class ElfMemImage {
 };
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 4739fbc5..a3dd893a 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_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Returns the program counter from signal context, nullptr if
@@ -53,6 +53,8 @@ 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(__riscv)
+    return reinterpret_cast<void*>(context->uc_mcontext.__gregs[REG_PC]);
 #elif defined(__s390__) && !defined(__s390x__)
     return reinterpret_cast<void*>(context->uc_mcontext.psw.addr & 0x7fffffff);
 #elif defined(__s390__) && defined(__s390x__)
@@ -151,5 +153,5 @@ void DumpPCAndFrameSizesAndStackTrace(
 }
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // namespace absl
diff --git a/absl/debugging/internal/examine_stack.h b/absl/debugging/internal/examine_stack.h
index 861db75d..39336913 100644
--- a/absl/debugging/internal/examine_stack.h
+++ b/absl/debugging/internal/examine_stack.h
@@ -17,8 +17,10 @@
 #ifndef ABSL_DEBUGGING_INTERNAL_EXAMINE_STACK_H_
 #define ABSL_DEBUGGING_INTERNAL_EXAMINE_STACK_H_
 
+#include "absl/base/config.h"
+
 namespace absl {
-inline namespace lts_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Returns the program counter from signal context, or nullptr if
@@ -34,7 +36,7 @@ void DumpPCAndFrameSizesAndStackTrace(
     void (*writerfn)(const char*, void*), void* writerfn_arg);
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 8dfd94aa..875ca6d9 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_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 namespace {
 
@@ -116,10 +116,11 @@ int GetSignalHandlerStackConsumption(void (*signal_handler)(int)) {
   // Set up the alt-signal-stack (and save the older one).
   stack_t sigstk;
   memset(&sigstk, 0, sizeof(sigstk));
-  stack_t old_sigstk;
   sigstk.ss_sp = altstack;
   sigstk.ss_size = kAlternateStackSize;
   sigstk.ss_flags = 0;
+  stack_t old_sigstk;
+  memset(&old_sigstk, 0, sizeof(old_sigstk));
   ABSL_RAW_CHECK(sigaltstack(&sigstk, &old_sigstk) == 0,
                  "sigaltstack() failed");
 
@@ -153,6 +154,15 @@ int GetSignalHandlerStackConsumption(void (*signal_handler)(int)) {
   int signal_handler_stack_consumption = GetStackConsumption(altstack);
 
   // Now restore the old alt-signal-stack and signal handlers.
+  if (old_sigstk.ss_sp == nullptr && old_sigstk.ss_size == 0 &&
+      (old_sigstk.ss_flags & SS_DISABLE)) {
+    // https://git.musl-libc.org/cgit/musl/commit/src/signal/sigaltstack.c?id=7829f42a2c8944555439380498ab8b924d0f2070
+    // The original stack has ss_size==0 and ss_flags==SS_DISABLE, but some
+    // versions of musl have a bug that rejects ss_size==0. Work around this by
+    // setting ss_size to MINSIGSTKSZ, which should be ignored by the kernel
+    // when SS_DISABLE is set.
+    old_sigstk.ss_size = MINSIGSTKSZ;
+  }
   ABSL_RAW_CHECK(sigaltstack(&old_sigstk, nullptr) == 0,
                  "sigaltstack() failed");
   ABSL_RAW_CHECK(sigaction(SIGUSR1, &old_sa1, nullptr) == 0,
@@ -168,7 +178,7 @@ int GetSignalHandlerStackConsumption(void (*signal_handler)(int)) {
 }
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 1eb37eef..5e60ec42 100644
--- a/absl/debugging/internal/stack_consumption.h
+++ b/absl/debugging/internal/stack_consumption.h
@@ -18,6 +18,8 @@
 #ifndef ABSL_DEBUGGING_INTERNAL_STACK_CONSUMPTION_H_
 #define ABSL_DEBUGGING_INTERNAL_STACK_CONSUMPTION_H_
 
+#include "absl/base/config.h"
+
 // The code in this module is not portable.
 // Use this feature test macro to detect its availability.
 #ifdef ABSL_INTERNAL_HAVE_DEBUGGING_STACK_CONSUMPTION
@@ -27,7 +29,7 @@
 #define ABSL_INTERNAL_HAVE_DEBUGGING_STACK_CONSUMPTION 1
 
 namespace absl {
-inline namespace lts_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Returns the stack consumption in bytes for the code exercised by
@@ -39,7 +41,7 @@ namespace debugging_internal {
 int GetSignalHandlerStackConsumption(void (*signal_handler)(int));
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 1c82d18a..80445bf4 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_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 namespace {
 
@@ -44,7 +44,7 @@ TEST(SignalHandlerStackConsumptionTest, MeasuresStackConsumption) {
 
 }  // namespace
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 14b6e6b0..411ea308 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_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return true;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 4f51d180..fffda968 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_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return false;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_DEBUGGING_INTERNAL_STACKTRACE_ARM_INL_H_
diff --git a/absl/debugging/internal/stacktrace_generic-inl.inc b/absl/debugging/internal/stacktrace_generic-inl.inc
index 39c47866..ac034c9f 100644
--- a/absl/debugging/internal/stacktrace_generic-inl.inc
+++ b/absl/debugging/internal/stacktrace_generic-inl.inc
@@ -16,6 +16,7 @@
 #include <cstring>
 
 #include "absl/debugging/stacktrace.h"
+#include "absl/base/attributes.h"
 
 // Sometimes, we can try to get a stack trace from within a stack
 // trace, because we don't block signals inside this code (which would be too
@@ -35,7 +36,7 @@ static __thread int recursive = 0;
 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.
-static int stacktraces_enabler = []() {
+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
@@ -86,13 +87,13 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
-inline namespace lts_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return true;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 ee6b38ff..2e7c2f40 100644
--- a/absl/debugging/internal/stacktrace_powerpc-inl.inc
+++ b/absl/debugging/internal/stacktrace_powerpc-inl.inc
@@ -236,13 +236,13 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
-inline namespace lts_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return true;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 b49a929a..5b8fb191 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_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return false;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 0cd8c339..9c2c5580 100644
--- a/absl/debugging/internal/stacktrace_win32-inl.inc
+++ b/absl/debugging/internal/stacktrace_win32-inl.inc
@@ -54,7 +54,7 @@ static RtlCaptureStackBackTrace_Function* const RtlCaptureStackBackTrace_fn =
 
 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) {
+                      const void*, int* min_dropped_frames) {
   int n = 0;
   if (!RtlCaptureStackBackTrace_fn) {
     // can't find a stacktrace with no function to call
@@ -73,13 +73,13 @@ static int UnwindImpl(void** result, int* sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
-inline namespace lts_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return false;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 ff0fd31f..bc320ff7 100644
--- a/absl/debugging/internal/stacktrace_x86-inl.inc
+++ b/absl/debugging/internal/stacktrace_x86-inl.inc
@@ -36,6 +36,8 @@
 
 #include "absl/base/internal/raw_logging.h"
 
+using absl::debugging_internal::AddressIsReadable;
+
 #if defined(__linux__) && defined(__i386__)
 // Count "push %reg" instructions in VDSO __kernel_vsyscall(),
 // preceeding "syscall" or "sysenter".
@@ -81,7 +83,7 @@ static int CountPushInstructions(const unsigned char *const addr) {
       // "mov reg,reg"
       if (addr[i + 1] == 0xE5) {
         // Found "mov %esp,%ebp".
-        return 0;  
+        return 0;
       }
       ++i;  // Skip register encoding byte.
     } else if (addr[i] == 0x0F &&
@@ -171,6 +173,7 @@ static void **NextStackFrame(void **old_fp, const void *uc) {
     static const unsigned char *kernel_rt_sigreturn_address = nullptr;
     static const unsigned char *kernel_vsyscall_address = nullptr;
     if (num_push_instructions == -1) {
+#ifdef ABSL_HAVE_VDSO_SUPPORT
       absl::debugging_internal::VDSOSupport vdso;
       if (vdso.IsPresent()) {
         absl::debugging_internal::VDSOSupport::SymbolInfo
@@ -199,6 +202,9 @@ static void **NextStackFrame(void **old_fp, const void *uc) {
       } else {
         num_push_instructions = 0;
       }
+#else  // ABSL_HAVE_VDSO_SUPPORT
+      num_push_instructions = 0;
+#endif  // ABSL_HAVE_VDSO_SUPPORT
     }
     if (num_push_instructions != 0 && kernel_rt_sigreturn_address != nullptr &&
         old_fp[1] == kernel_rt_sigreturn_address) {
@@ -222,7 +228,7 @@ static void **NextStackFrame(void **old_fp, const void *uc) {
           // "double fault" in case we hit the first fault due to e.g. stack
           // corruption.
           void *const reg_esp2 = reg_esp[num_push_instructions - 1];
-          if (absl::debugging_internal::AddressIsReadable(reg_esp2)) {
+          if (AddressIsReadable(reg_esp2)) {
             // Alleged %esp is readable, use it for further unwinding.
             new_fp = reinterpret_cast<void **>(reg_esp2);
           }
@@ -274,7 +280,7 @@ static void **NextStackFrame(void **old_fp, const void *uc) {
     // Note: NextStackFrame<false>() is only called while the program
     //       is already on its last leg, so it's ok to be slow here.
 
-    if (!absl::debugging_internal::AddressIsReadable(new_fp)) {
+    if (!AddressIsReadable(new_fp)) {
       return nullptr;
     }
   }
@@ -328,13 +334,13 @@ static int UnwindImpl(void **result, int *sizes, int max_depth, int skip_count,
 }
 
 namespace absl {
-inline namespace lts_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 bool StackTraceWorksForTest() {
   return true;
 }
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 151bc77c..5d0858b5 100644
--- a/absl/debugging/internal/symbolize.h
+++ b/absl/debugging/internal/symbolize.h
@@ -21,6 +21,8 @@
 #include <cstddef>
 #include <cstdint>
 
+#include "absl/base/config.h"
+
 #ifdef ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE
 #error ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE cannot be directly set
 #elif defined(__ELF__) && defined(__GLIBC__) && !defined(__native_client__) && \
@@ -33,7 +35,7 @@
 #include <string>
 
 namespace absl {
-inline namespace lts_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 // Iterates over all sections, invoking callback on each with the section name
@@ -52,13 +54,13 @@ bool GetSectionHeaderByName(int fd, const char *name, size_t name_len,
                             ElfW(Shdr) *out);
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE
 
 namespace absl {
-inline namespace lts_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 struct SymbolDecoratorArgs {
@@ -120,7 +122,7 @@ bool GetFileMappingHint(const void** start,
                         const char** filename);
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // 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 fa88e1d8..1e8a78ac 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_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 namespace debugging_internal {
 
 ABSL_CONST_INIT
@@ -188,7 +188,7 @@ static class VDSOInitHelper {
 } vdso_init_helper;
 
 }  // namespace debugging_internal
-}  // inline namespace lts_2019_08_08
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_HAVE_VDSO_SUPPORT
diff --git a/absl/debugging/internal/vdso_support.h b/absl/debugging/internal/vdso_support.h
index bc5fdb11..6562c6c2 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_2019_08_08 {
+ABSL_NAMESPACE_BEGIN
 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_2019_08_08
+ABSL_NAMESPACE_END
 }  // namespace absl
 
 #endif  // ABSL_HAVE_ELF_MEM_IMAGE