@@ 0,0 1,60 @@
+https://sources.debian.org/data/main/a/abseil/0~20200923.3-2/debian/patches/cpu-frequency.diff
+This patch is taken from Debian instead of the upstream URL because the
+upstream URL contains far more changes than occur in this patch.
+
+It was then modified to also work for armhf.
+
+From: Benjamin Barenblat <bbaren@google.com>
+Subject: Ignore missing CPU frequency on more architectures
+Forwarded: yes
+Applied-Upstream: https://github.com/abseil/abseil-cpp/commit/1918ad2ae38aa32c74b558b322479a8efdd76363
+
+Linux on MIPS, PA-RISC, RISC-V, and SystemZ doesn’t expose the nominal CPU
+frequency via /sys, so don’t worry if `NominalCPUFrequency` returns 1.0 on those
+platforms.
+
+Some POWER machines expose the CPU frequency; others do not. Since we can’t
+predict which type of machine the tests will run on, simply disable testing for
+`NominalCPUFrequency` on POWER.
+
+The author works at Google. Upstream applied this patch as Piper revision
+347079873 and exported it to GitHub; the Applied-Upstream URL above points to
+the exported commit.
+
+--- a/absl/base/internal/sysinfo_test.cc
++++ b/absl/base/internal/sysinfo_test.cc
+@@ -37,17 +37,28 @@ TEST(SysinfoTest, NumCPUs) {
+       << "NumCPUs() should not have the default value of 0";
+ }
+ 
++// Ensure that NominalCPUFrequency returns a reasonable value, or 1.00 on
++// platforms where the CPU frequency is not available through sysfs.
++//
++// POWER is particularly problematic here; some Linux kernels expose the CPU
++// frequency, while others do not. Since we can't predict a priori what a given
++// machine is going to do, just disable this test on POWER on Linux.
++#if !(defined(__linux) && (defined(__ppc64__) || defined(__PPC64__)))
+ TEST(SysinfoTest, NominalCPUFrequency) {
+-#if !(defined(__aarch64__) && defined(__linux__)) && !defined(__EMSCRIPTEN__)
+-  EXPECT_GE(NominalCPUFrequency(), 1000.0)
+-      << "NominalCPUFrequency() did not return a reasonable value";
+-#else
+-  // Aarch64 cannot read the CPU frequency from sysfs, so we get back 1.0.
+-  // Emscripten does not have a sysfs to read from at all.
++  // Linux only exposes the CPU frequency on certain architectures, and
++  // Emscripten doesn't expose it at all.
++#if defined(__linux__) &&                                                  \
++        (defined(__aarch64__) || defined(__hppa__) || defined(__mips__) || \
++         defined(__arm__) || defined(__riscv) || defined(__s390x__)) ||                        \
++    defined(__EMSCRIPTEN__)
+   EXPECT_EQ(NominalCPUFrequency(), 1.0)
+       << "CPU frequency detection was fixed! Please update unittest.";
++#else
++  EXPECT_GE(NominalCPUFrequency(), 1000.0)
++      << "NominalCPUFrequency() did not return a reasonable value";
+ #endif
+ }
++#endif
+ 
+ TEST(SysinfoTest, GetTID) {
+   EXPECT_EQ(GetTID(), GetTID());  // Basic compile and equality test.


@@ 0,0 1,86 @@
+This patch is taken from upstream and helps the test pass on all architectures.
+
+The adjustment to absl/numeric/internal/bits.h was removed since the file
+didn't appear in the git checkout.
+
+From b0735979d778a768caee207f01f327535cbd2140 Mon Sep 17 00:00:00 2001
+From: Abseil Team <absl-team@google.com>
+Date: Tue, 2 Mar 2021 14:28:07 -0800
+Subject: [PATCH] Export of internal Abseil changes
+
+--
+a74bdb72c3a6983e08a805938dd0e20e97d55bba by Abseil Team <absl-team@google.com>:
+
+Fix typo: calcualte -> calculate
+
+PiperOrigin-RevId: 360515509
+
+--
+3ddf8ac194e81a13e9de095e59dd061c1beacfe3 by Benjamin Barenblat <bbaren@google.com>:
+
+Make tests tolerant of FMA contraction
+
+Weaken Duration.ToDoubleSecondsCheckEdgeCases and
+Duration.ToDoubleSecondsCheckRandom to make them less sensitive to fused
+multiply/add contraction.
+
+PiperOrigin-RevId: 360297653
+GitOrigin-RevId: a74bdb72c3a6983e08a805938dd0e20e97d55bba
+Change-Id: I0c55383bc13040ea77511c4130d142368103dc57
+---
+ absl/numeric/internal/bits.h |  2 +-
+ absl/time/duration_test.cc   | 18 +++++++++++-------
+ 2 files changed, 12 insertions(+), 8 deletions(-)
+
+diff --git a/absl/time/duration_test.cc b/absl/time/duration_test.cc
+index 4d85a2c4f45..fb28fa987f6 100644
+--- a/absl/time/duration_test.cc
++++ b/absl/time/duration_test.cc
+@@ -1369,10 +1369,13 @@ TEST(Duration, SmallConversions) {
+   EXPECT_THAT(ToTimeval(absl::Nanoseconds(2000)), TimevalMatcher(tv));
+ }
+ 
+-void VerifySameAsMul(double time_as_seconds, int* const misses) {
++void VerifyApproxSameAsMul(double time_as_seconds, int* const misses) {
+   auto direct_seconds = absl::Seconds(time_as_seconds);
+   auto mul_by_one_second = time_as_seconds * absl::Seconds(1);
+-  if (direct_seconds != mul_by_one_second) {
++  // These are expected to differ by up to one tick due to fused multiply/add
++  // contraction.
++  if (absl::AbsDuration(direct_seconds - mul_by_one_second) >
++      absl::time_internal::MakeDuration(0, 1u)) {
+     if (*misses > 10) return;
+     ASSERT_LE(++(*misses), 10) << "Too many errors, not reporting more.";
+     EXPECT_EQ(direct_seconds, mul_by_one_second)
+@@ -1384,7 +1387,8 @@ void VerifySameAsMul(double time_as_seconds, int* const misses) {
+ // For a variety of interesting durations, we find the exact point
+ // where one double converts to that duration, and the very next double
+ // converts to the next duration.  For both of those points, verify that
+-// Seconds(point) returns the same duration as point * Seconds(1.0)
++// Seconds(point) returns a duration near point * Seconds(1.0). (They may
++// not be exactly equal due to fused multiply/add contraction.)
+ TEST(Duration, ToDoubleSecondsCheckEdgeCases) {
+   constexpr uint32_t kTicksPerSecond = absl::time_internal::kTicksPerSecond;
+   constexpr auto duration_tick = absl::time_internal::MakeDuration(0, 1u);
+@@ -1423,8 +1427,8 @@ TEST(Duration, ToDoubleSecondsCheckEdgeCases) {
+         }
+         // Now low_edge is the highest double that converts to Duration d,
+         // and high_edge is the lowest double that converts to Duration after_d.
+-        VerifySameAsMul(low_edge, &misses);
+-        VerifySameAsMul(high_edge, &misses);
++        VerifyApproxSameAsMul(low_edge, &misses);
++        VerifyApproxSameAsMul(high_edge, &misses);
+       }
+     }
+   }
+@@ -1444,8 +1448,8 @@ TEST(Duration, ToDoubleSecondsCheckRandom) {
+   int misses = 0;
+   for (int i = 0; i < 1000000; ++i) {
+     double d = std::exp(uniform(gen));
+-    VerifySameAsMul(d, &misses);
+-    VerifySameAsMul(-d, &misses);
++    VerifyApproxSameAsMul(d, &misses);
++    VerifyApproxSameAsMul(-d, &misses);
+   }
+ }
+ 


@@ 0,0 1,42 @@
+From e2b1bab19a782cb62bb010d1c2925ab7314fb113 Mon Sep 17 00:00:00 2001
+diff --git a/absl/base/internal/strerror.cc b/absl/base/internal/strerror.cc
+index d66ba120..0d6226fd 100644
+--- a/absl/base/internal/strerror.cc
++++ b/absl/base/internal/strerror.cc
+@@ -51,7 +51,6 @@ const char* StrErrorAdaptor(int errnum, char* buf, size_t buflen) {
+ }
+ 
+ std::string StrErrorInternal(int errnum) {
+-  absl::base_internal::ErrnoSaver errno_saver;
+   char buf[100];
+   const char* str = StrErrorAdaptor(errnum, buf, sizeof buf);
+   if (*str == '\0') {
+@@ -76,6 +75,7 @@ std::array<std::string, kSysNerr>* NewStrErrorTable() {
+ }  // namespace
+ 
+ std::string StrError(int errnum) {
++  absl::base_internal::ErrnoSaver errno_saver;
+   static const auto* table = NewStrErrorTable();
+   if (errnum >= 0 && errnum < static_cast<int>(table->size())) {
+     return (*table)[errnum];
+diff --git a/absl/base/internal/strerror_test.cc b/absl/base/internal/strerror_test.cc
+index a53da97f..e32d5b5c 100644
+--- a/absl/base/internal/strerror_test.cc
++++ b/absl/base/internal/strerror_test.cc
+@@ -62,12 +62,14 @@ TEST(StrErrorTest, MultipleThreads) {
+       ++counter;
+       errno = ERANGE;
+       const std::string value = absl::base_internal::StrError(i);
++      // EXPECT_* could change errno. Stash it first.
++      int check_err = errno;
++      EXPECT_THAT(check_err, Eq(ERANGE));
+       // Only the GNU implementation is guaranteed to provide the
+       // string "Unknown error nnn". POSIX doesn't say anything.
+       if (!absl::StartsWith(value, "Unknown error ")) {
+-        EXPECT_THAT(absl::base_internal::StrError(i), Eq(expected_strings[i]));
++        EXPECT_THAT(value, Eq(expected_strings[i]));
+       }
+-      EXPECT_THAT(errno, Eq(ERANGE));
+     }
+   };
+