GH-51215: [C++] Migrate remaining datetime consumers to the chrono shim by rok · Pull Request #51216 · apache/arrow

rok · 2026-09-07T14:48:46Z

Rationale for this change

Follow up on #48593 / #48601 - migrate remaining uses of arrow_vendored::date to arrow::internal::chrono, using std::chrono where supported.

What changes are included in this PR?

Route core calendar, parsing, formatting, and Gandiva callers through arrow::internal::chrono.
Move backend selection into a shared chrono_config_internal.h, which is also used to guard the vendored timezone sources (datetime.cpp, datetime_ios.mm) so standard-library builds don't compile a second timezone implementation.
Enable std::chrono on non-Windows with libstdc++ >= 16.2 (earlier versions are affected by https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116110 and keep using the vendored library).
Move strftime-to-std::format translation into TimestampFormatter, preserving Arrow's existing strftime syntax (%Q/%q, %n/%t, unknown directives as literals, braces, etc.).
R: set_timezone_database is a no-op when the timezone database isn't configurable (e.g. MinGW builds using std::chrono).
CI: add a Debian experimental GCC 16 crossbow job to exercise the std::chrono path on Linux.

Are these changes tested?

Yes. By existing tests, new tests for strftime format translation and formatter stream state, and the new GCC 16 crossbow job.

Are there any user-facing changes?

Yes, for builds that select the std::chrono backend (MSVC, MinGW with C++20 timezone support, and Linux with libstdc++ >= 16.2):

arrow::Initialize() with GlobalOptions::timezone_db_path (deprecated since 24.0.0) now returns Invalid, and RuntimeInfo::using_os_timezone_db is true. On MSVC this means the deprecated pyarrow.set_timezone_db_path now raises instead of silently configuring an unused database.
libarrow no longer exports the arrow_vendored::date timezone functions (locate_zone, current_zone, reload_tzdb, ...) since the vendored timezone sources are not compiled. Downstream code calling these directly will fail to link against such builds. Calendar types in arrow/vendored/datetime.h are header-only and unaffected.
arrow/util/chrono_internal.h and arrow/util/chrono_config_internal.h are now installed, as they are included by the public formatting.h and value_parsing.h headers.

AI disclosure: this was in large part generated by AI. However I am familiar with the codebase somewhat and have reviewed proposed changes manually.

GitHub Issue: [C++][Gandiva] Reduce dependency on vendored date.h library #51215

github-actions · 2026-09-07T14:49:12Z

⚠️ GitHub issue #51215 has been automatically assigned in GitHub to PR creator.

rok · 2026-09-07T16:12:22Z

@github-actions crossbow submit verify-rc-source-windows test-build-vcpkg-win

github-actions · 2026-09-07T16:15:02Z

Revision: d22fc96

Submitted crossbow builds: ursacomputing/crossbow @ actions-ef7574f790

Task	Status
test-build-vcpkg-win
verify-rc-source-windows

rok · 2026-09-07T16:19:25Z

After #51211 is merged we can completely move to the arrow::internal::chrono shim, which will make it easier to reason about which library is being used for temporal operations and eventually move off of the vendored date.h.

rok · 2026-09-07T17:38:35Z

@github-actions crossbow submit verify-rc-source-windows test-build-vcpkg-win

github-actions · 2026-09-07T17:40:50Z

Revision: ef7d5fe

Submitted crossbow builds: ursacomputing/crossbow @ actions-41c0a4fab7

Task	Status
test-build-vcpkg-win
verify-rc-source-windows

rok · 2026-09-07T18:58:32Z

@github-actions crossbow submit verify-rc-source-windows test-build-vcpkg-win

github-actions · 2026-09-07T19:00:43Z

Revision: a5d7ef9

Submitted crossbow builds: ursacomputing/crossbow @ actions-1c32742fcc

Task	Status
test-build-vcpkg-win
verify-rc-source-windows

rok · 2026-09-07T22:51:08Z

@github-actions crossbow submit verify-rc-source-windows test-build-vcpkg-win

rok · 2026-09-07T22:53:02Z

@pitrou does approach of this PR make sense? Especialy cpp/src/arrow/util/chrono_config_internal.h. If it does I'll polish it and push it to review.

github-actions · 2026-09-07T22:53:14Z

Revision: fdcaf7e

Submitted crossbow builds: ursacomputing/crossbow @ actions-6ed6db4ecf

Task	Status
test-build-vcpkg-win
verify-rc-source-windows

pitrou · 2026-09-08T08:33:32Z

@pitrou does approach of this PR make sense? Especialy cpp/src/arrow/util/chrono_config_internal.h. If it does I'll polish it and push it to review.

I think it does.

rok · 2026-09-08T16:54:57Z

@github-actions crossbow submit test-r-fedora-clang test-r-linux-as-cran test-r-alpine-linux-cran test-r-macos-as-cran r-binary-packages verify-rc-source-windows test-build-vcpkg-win

github-actions · 2026-09-08T16:57:20Z

Revision: 09d3c61

Submitted crossbow builds: ursacomputing/crossbow @ actions-51d00219e4

Task	Status
r-binary-packages
test-build-vcpkg-win
test-r-alpine-linux-cran
test-r-fedora-clang
test-r-linux-as-cran
test-r-macos-as-cran
verify-rc-source-windows

- R: skip set_timezone_database when the timezone database is managed by the OS or standard library, avoiding a startup error on MinGW builds - Clarify the Initialize() error message for standard-library backends - Document backend selection caveats (runtime libstdc++, MinGW, installed headers, vendored timezone symbols not exported) - Avoid a global namespace alias in gandiva's epoch_time_point.h - Report an error when TimestampFormatter's stream sentry fails

rok · 2026-09-30T07:41:24Z

@github-actions crossbow submit test-debian-experimental-cpp-gcc-16

github-actions · 2026-09-30T07:43:38Z

Revision: 14c50d8

Submitted crossbow builds: ursacomputing/crossbow @ actions-76ecbaf520

Task	Status
test-debian-experimental-cpp-gcc-16

raulcd · 2026-09-30T08:49:00Z

The failure on test-debian-experimental-cpp-gcc-16 seems related to the last commit on main coming from:

GH-51329: [C++][CI] Test static linking with S3 and fix Azure/GCS dependencies on static builds #51280

Testing test-debian-experimental-cpp-gcc-15 as it's probably reproducible there and might be failing on main.

raulcd · 2026-09-30T08:49:57Z

@github-actions crossbow submit test-debian-experimental-cpp-gcc-15

github-actions · 2026-09-30T08:52:08Z

Revision: 14c50d8

Submitted crossbow builds: ursacomputing/crossbow @ actions-3fd704e3af

Task	Status
test-debian-experimental-cpp-gcc-15

rok · 2026-09-30T09:51:20Z

The failure on test-debian-experimental-cpp-gcc-16 seems related to the last commit on main coming from:

GH-51329: [C++][CI] Test static linking with S3 and fix Azure/GCS dependencies on static builds #51280

Testing test-debian-experimental-cpp-gcc-15 as it's probably reproducible there and might be failing on main.

The aim with gcc-16 is to test std::chrono on linux (no other compilers we have on linux will currently use that codepath). I can wait for GH-51329 to merge, rebase and check. I don't really want to add test-debian-experimental-cpp-gcc-15 job and this doesn't really block review.

raulcd · 2026-09-30T09:58:16Z

Agree, sorry if it was not clear, the failures are completely unrelated to this PR and this PR can be reviewed I was just validating the failure was also happening on gcc15. I've opened an issue to fix those failures (which also happen on main) here:

[C++][CI] New arrow-example-s3-static check fails linking abseil #51651

rok · 2026-09-30T10:27:48Z

@pitrou I addressed you comments and this is ready for another round. That said - is this change something we would want to merge before the release or rather afterwards? I'd defer to your judgement.

pitrou · 2026-09-30T12:14:29Z

@github-actions crossbow submit -g cpp

github-actions · 2026-09-30T12:17:43Z

Revision: fd2bb12

Submitted crossbow builds: ursacomputing/crossbow @ actions-89610adff7

Task	Status
example-cpp-minimal-build-static
example-cpp-minimal-build-static-system-dependency
example-cpp-tutorial
test-build-cpp-fuzz
test-conda-cpp
test-conda-cpp-valgrind
test-debian-13-cpp-amd64
test-debian-13-cpp-i386
test-debian-experimental-cpp-gcc-15
test-debian-experimental-cpp-gcc-16
test-fedora-42-cpp
test-ubuntu-22.04-cpp
test-ubuntu-22.04-cpp-bundled
test-ubuntu-22.04-cpp-emscripten
test-ubuntu-22.04-cpp-no-threading
test-ubuntu-24.04-cpp
test-ubuntu-24.04-cpp-gcc-13-bundled
test-ubuntu-24.04-cpp-gcc-14
test-ubuntu-24.04-cpp-minimal-with-formats
test-ubuntu-24.04-cpp-thread-sanitizer

pitrou · 2026-09-30T12:15:00Z

 }

+#if ARROW_USE_STD_CHRONO
+TEST(TimestampFormatterTest, CoalesceChronoFields) {


Could you add a comment explaining what this is about?

pitrou · 2026-09-30T12:16:07Z

+}
+#endif
+
+TEST(TimestampFormatterTest, ReuseFormatter) {


Same, explain why this is useful?

pitrou · 2026-09-30T12:18:23Z

                   &options_earliest);
 }

+#if ARROW_USE_STD_CHRONO


Some of these tests are not compute-specific, can we move them to a more appropriate place? For example arrow/util/time_test.cc

pitrou · 2026-09-30T12:18:40Z

+  }
+}
+
+TEST(TimestampFormatterTest, NanosecondRangeLimits) {


Do we test for overflow somewhere?

pitrou · 2026-09-30T12:19:05Z

+  EXPECT_EQ(result, "763145224192 ns");
+}
+
+TEST(TimestampFormatterTest, StreamState) {


What is this for exactly? Is it useful? if so, add a comment?

pitrou · 2026-09-30T12:26:15Z

+  const auto append_literal = [&](char value) {
+    // Braces and literal percent signs must stay outside chrono replacement fields.
+    if (value == '{' || value == '}' || value == '%') close_zoned_field();
+    AppendEscapedLiteral(&out, value);


If this is the single call site of AppendEscapedLiteral, perhaps it needn't be a separate function at all?

pitrou · 2026-09-30T12:29:48Z

+                                     ? local_time - local_day
+                                     : std::chrono::days{1} - (local_day - local_time);
+        const auto time_of_day_count = time_of_day.count();
+        const std::ostream::sentry sentry(bufstream);


Hmm, what is this for/how this snippet work? Can you add explanatory comments?

pitrou · 2026-09-30T12:29:58Z

+              std::make_format_args(zt, time_of_day, time_of_day_count));
+          if (end.failed()) bufstream.setstate(std::ios::badbit);
+        } else {
+          bufstream.setstate(std::ios::badbit);


pitrou · 2026-09-30T12:31:18Z

+
 template <typename Duration>
 struct TimestampFormatter {
+  static std::string PrepareFormat(const std::string& format) {


Can you make this method protected and move it towards the end of the struct for clarity?

pitrou · 2026-09-30T12:31:41Z

+    return detail::ToChronoFormat(
+        format.c_str(), std::ratio_equal_v<typename Precision::period, std::micro>);


Please add parameter name when it's not obvious.

Suggested change

return detail::ToChronoFormat(

format.c_str(), std::ratio_equal_v<typename Precision::period, std::micro>);

return detail::ToChronoFormat(

format.c_str(), /*xxx=*/ std::ratio_equal_v<typename Precision::period, std::micro>);

github-actions Bot added Component: C++ Component: Gandiva awaiting committer review Awaiting committer review labels Sep 7, 2026

rok force-pushed the gh-51215-chrono-shim branch 2 times, most recently from 3e23a57 to d22fc96 Compare September 7, 2026 15:50

rok force-pushed the gh-51215-chrono-shim branch from ef7d5fe to a5d7ef9 Compare September 7, 2026 18:58

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rok force-pushed the gh-51215-chrono-shim branch 3 times, most recently from b69f711 to fdcaf7e Compare September 7, 2026 22:48

rok force-pushed the gh-51215-chrono-shim branch 4 times, most recently from dd9b10c to 09d3c61 Compare September 8, 2026 16:52

rok force-pushed the gh-51215-chrono-shim branch from 09d3c61 to 6dbcec4 Compare September 8, 2026 17:23

restore format as const

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apacheGH-51215: [C++] Avoid overflow in timestamp time-of-day formatting

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pitrou added the CI: Extra: C++ Run extra C++ CI label Sep 30, 2026

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		return detail::ToChronoFormat(
		format.c_str(), std::ratio_equal_v<typename Precision::period, std::micro>);

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