NEWS: add entry about disabling wildcard support by default

Author: lazka

web/docs/c.md

@@ -11,7 +11,7 @@ With mingw-w64, there are three ways wildcard expansion can be configured:
 
 1. mingw-w64 can be configured at build time to either enable or disable wildcard expansion by default via the `--enable-wildcard` configure flags. This can to be overridden on a per .exe basis by the user.
 
-    Currently wildcard expansion is enabled by default in MSYS2.
+    Wildcard expansion is disabled by default in MSYS2.
 
 2. You can set `_dowildcard` in your source code to either `0` or `-1` to disable or enable wildcard expansion.
 
@@ -30,3 +30,10 @@ With mingw-w64, there are three ways wildcard expansion can be configured:
     # To force-disable wildcard expansion
     cc main.c $(cc -print-file-name=CRT_noglob.o)
     ```
+
+### Changelog
+
+* Starting with 2024-11-03 we have changed mingw-w64 to to disable wildcard
+handling by default. You can still enable it on a per application basis as
+described above. For more info on the change see [the news
+entry](../news.md#2024-11-03---disabling-mingw-w64-wildcard-support-by-default).

web/news.md

@@ -5,6 +5,42 @@ summary: Important events happening.
 
 This page lists important changes or issues affecting MSYS2 users. We also post them to [Twitter](https://twitter.com/msys2org) and [Mastodon](https://fosstodon.org/@msys2org), including some not-so-important things :)
 
+### 2024-11-03 - Disabling mingw-w64 wildcard support by default
+
+For historical reasons MSYS2 enabled wildcard support in mingw-w64 at build
+time. This means that every built executable had wildcard support enabled by
+default, unless it explicitly opted out. Wildcard support in this case means
+that program arguments containing `?`and `*` can be expanded to one or more file
+paths if the pattern happens to match paths of files on disk. Note that this
+happens directly in the target program, not in a shell beforehand.
+
+This expansion has several problems:
+
+* Behave differently than MSVC built executables
+* It's confusing to users when wildcard handling is accidentally triggered. For
+  example, passing a regex as an argument to a CLI tool that starts matching
+  random files, breaking the pattern.
+* It may have security implications if arguments to executables are forwarded
+  from user-controlled input, in which case an argument could expand to a
+  different string depending on the files present on the filesystem.
+
+Given all this, we have decided to disable wildcard handling by default. This
+means that any package and executable that is built after this change will get
+the new default behavior.
+
+```console
+$ python -c 'import sys; print(sys.argv)' '*a.txt' # before
+['-c', 'a.txt', 'aaaa.txt', 'bla.txt']
+$ python -c 'import sys; print(sys.argv)' '*a.txt' # after
+['-c', '*a.txt']
+```
+
+Our hope/assumption is that this will not affect many users, as most will rely
+on globbing at a higher level, be it bash, or build systems. If you experience
+any problems, please let us know. See also [the
+documentation](./docs/c.md#expanding-wildcard-arguments) on how to force
+wildcard handling for your applications even after this change.
+
 ### 2024-09-23 - Starting to drop the CLANG32 environment
 
 9 months ago we started to reduce the number of packages for the 32-bit