[FFmpeg-cvslog] configure: Clearly state that MSYS native builds are discouraged

[Luca Barbato]

ffmpeg | branch: master | Luca Barbato <lu_zero at gentoo.org> | Sat Nov 21 18:51:11 2015 +0100| [afdff8008149515afebf9992eae84be7d76e6b1e] | committer: Luca Barbato

configure: Clearly state that MSYS native builds are discouraged

MSYS, as per cygwin, by default uses a custom posix abstraction
in the form of a "msys2.dll". Programs build that way are harder to
distribute and use.

MSYS2 provides alternate launcher scripts that provide a MINGW
environment nearly out of box.

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=afdff8008149515afebf9992eae84be7d76e6b1e
---

 configure |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/configure b/configure
index f5a9a26..6640f2f 100755
--- a/configure
+++ b/configure
@@ -3647,6 +3647,9 @@ case $target_os in
         enabled_any pic shared ||
             { check_cflags -mdynamic-no-pic && add_asflags -mdynamic-no-pic; }
         ;;
+    msys*)
+        die "Native MSYS builds are discouraged, please use the MINGW environment.";
+        ;;
     mingw32*)
         if test $target_os = "mingw32ce"; then
             disable network