Merge branch 'doc-3.15-std-fix' into release-3.16
Merge-request: !4574
diff --git a/Help/release/3.15.rst b/Help/release/3.15.rst
index 957e6e9..e68e7d3 100644
--- a/Help/release/3.15.rst
+++ b/Help/release/3.15.rst
@@ -332,6 +332,15 @@
Other Changes
=============
+* If a feature specified by :command:`target_compile_features` is available
+ in the compiler's default standard level, CMake 3.14 and below incorrectly
+ added unnecessary ``-std=`` flags that could lower the standard level.
+ This bug has been fixed in CMake 3.15. This behavior change may expose
+ bugs in existing projects that were relying on undocumented implementation
+ details. Specifying compile features only ensures that the compiler runs
+ in a mode that has those features, not that any specific standard level is
+ used or explicit ``-std=`` flag passed.
+
* CMake learned how to compile C++14 with the IBM AIX XL compiler
and the SunPro compiler and to compile C++20 with the AppleClang compiler.
