Export of internal Abseil changes.

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f9f068aa8a260dc576398e47b8e4540902e41358 by Derek Mauro <dmauro@google.com>:

Fix test string with embedded NUL. Currently parses as octal.

PiperOrigin-RevId: 237088193

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d271ffdd3f450f817f6d30e98ff39d439aaf3a98 by Abseil Team <absl-team@google.com>:

Make symbolizer examine any mapping with read+exec permission regardless of 'w' bit.

PiperOrigin-RevId: 237056461

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af315f8306d36a7367a452fd0b58cafdbf20719d by Abseil Team <absl-team@google.com>:

Switch comments referencing base:: CondVar and Mutex to absl::.

PiperOrigin-RevId: 236917884

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c624d5d1c0bdb917bff5e651ba40599472f84e0e by Gennadiy Rozental <rogeeff@google.com>:

Internal change

PiperOrigin-RevId: 236898300

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3cdc82429af964846d1152f49148abc61d196a4b by Samuel Benzaquen <sbenza@google.com>:

Make the `long double` overload if AbslHashValue a template to avoid invalid
conversions with implicit operators.

This overload was never meant to capture anything other than `long double` and any current caller to it that wasn't a `long double` is potentially a bug.
In particular, any type with an implicit `bool` conversion is calling this
overload instead of trying to find a hash<> specialization, thus causing
pretty bad hash behavior.

PiperOrigin-RevId: 236877073
GitOrigin-RevId: f9f068aa8a260dc576398e47b8e4540902e41358
Change-Id: If9cc008dd814f0ca06ed881f612c06575f1f7137

absl/debugging/failure_signal_handler_test.cc

@@ -133,7 +133,8 @@ constexpr int kFailureSignals[] = {
 };
 
 std::string SignalParamToString(const ::testing::TestParamInfo<int>& info) {
-  std::string result = absl::debugging_internal::FailureSignalToString(info.param);
+  std::string result =
+      absl::debugging_internal::FailureSignalToString(info.param);
   if (result.empty()) {
     result = absl::StrCat(info.param);
   }

absl/debugging/internal/symbolize.h

@@ -20,7 +20,6 @@
 
 #include <cstddef>
 #include <cstdint>
-#include "absl/base/port.h"  // Needed for string vs std::string
 
 #ifdef ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE
 #error ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE cannot be directly set
@@ -42,9 +41,9 @@ namespace debugging_internal {
 // Returns true on success; otherwise returns false in case of errors.
 //
 // This is not async-signal-safe.
-bool ForEachSection(
-    int fd, const std::function<bool(const std::string& name, const ElfW(Shdr) &)>&
-                callback);
+bool ForEachSection(int fd,
+                    const std::function<bool(const std::string& name,
+                                             const ElfW(Shdr) &)>& callback);
 
 // Gets the section header for the given name, if it exists. Returns true on
 // success. Otherwise, returns false.

absl/debugging/symbolize_elf.inc

@@ -925,6 +925,14 @@ static const char *GetHex(const char *start, const char *end,
   return p;
 }
 
+// Normally we are only interested in "r?x" maps.
+// On the PowerPC, function pointers point to descriptors in the .opd
+// section.  The descriptors themselves are not executable code, so
+// we need to relax the check below to "r??".
+static bool ShouldUseMapping(const char *const flags) {
+  return flags[0] == 'r' && (kPlatformUsesOPDSections || flags[2] == 'x');
+}
+
 // Read /proc/self/maps and run "callback" for each mmapped file found.  If
 // "callback" returns false, stop scanning and return true. Else continue
 // scanning /proc/self/maps. Return true if no parse error is found.
@@ -994,12 +1002,8 @@ static ABSL_ATTRIBUTE_NOINLINE bool ReadAddrMap(
       return false;
     }
 
-    // Check flags.  Normally we are only interested in "r-x" maps.  On
-    // the PowerPC, function pointers point to descriptors in the .opd
-    // section.  The descriptors themselves are not executable code.  So
-    // we need to relax the check below to "r**".
-    if (memcmp(flags_start, "r-x", 3) != 0 &&  // Not a "r-x" map.
-        !(kPlatformUsesOPDSections && flags_start[0] == 'r')) {
+    // Check flags.
+    if (!ShouldUseMapping(flags_start)) {
       continue;  // We skip this map.
     }
     ++cursor;  // Skip ' '.