[libcxx][span] Implement P1976R2
This resolves the NB comment about the construction of a fixed-size span
from a dynamic range.
Differential Revision: https://reviews.llvm.org/D74577
Cr-Mirrored-From: https://chromium.googlesource.com/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 6d2599e4f776d0cd88438cb82a00c4fc25cc3f67
diff --git a/docs/FeatureTestMacroTable.rst b/docs/FeatureTestMacroTable.rst
index 937683d..77c7c68 100644
--- a/docs/FeatureTestMacroTable.rst
+++ b/docs/FeatureTestMacroTable.rst
@@ -198,6 +198,8 @@
------------------------------------------------- -----------------
``__cpp_lib_ranges`` *unimplemented*
------------------------------------------------- -----------------
+ ``__cpp_lib_span`` ``202002L``
+ ------------------------------------------------- -----------------
``__cpp_lib_three_way_comparison`` *unimplemented*
------------------------------------------------- -----------------
``__cpp_lib_to_array`` ``201907L``