[libc++][format] Updates feature-test macros.
During the discussion on the SG-10 mailinglist regarding the format
feature-test macros voted in during the last plenary it turns out libc++
can't mark the format feature-test macro as implemented.
According to
https://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations#__cpp_lib_format
the not yet implemented paper
P1361R2 Integration of chrono with text formatting
affects the feature test macro.
Note that P1361R2 doesn't mention the feature-test macro nor is there an
LWG-issue to address the issue. The reporter of the issue didn't recall
where this requirement exactly has been decided.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D133271
NOKEYCHECK=True
GitOrigin-RevId: b490c8a6623c6a32cebf45567c467d38c3285fb9
diff --git a/docs/FeatureTestMacroTable.rst b/docs/FeatureTestMacroTable.rst
index 8d38beb..11bff15 100644
--- a/docs/FeatureTestMacroTable.rst
+++ b/docs/FeatureTestMacroTable.rst
@@ -234,7 +234,7 @@
------------------------------------------------- -----------------
``__cpp_lib_execution`` *unimplemented*
------------------------------------------------- -----------------
- ``__cpp_lib_format`` ``202106L``
+ ``__cpp_lib_format`` *unimplemented*
------------------------------------------------- -----------------
``__cpp_lib_generic_unordered_lookup`` ``201811L``
------------------------------------------------- -----------------