[FFmpeg-cvslog] configure: Fix a regression when probing link.exe

[Alexander Strasser]

ffmpeg | branch: master | Alexander Strasser <eclipse7 at gmx.net> | Sat Jun 21 11:13:22 2025 +0200| [204d03c803de6a656f8adba7f198383ee3751318] | committer: Martin Storsjö

configure: Fix a regression when probing link.exe

The version ident is printed on stdout for link.exe and redirecting
stdout to /dev/null will cause the output of link.exe to be paged.

This caused configure to hang for some configurations and by
extension some FATE clients. You might want to check if you run
affected configurations automated in FATE clients or similar setups.

Fixes: 45a30e03613a3c63d74a40f7ac86ce28dce14ff8
Signed-off-by: Martin Storsjö <martin at martin.st>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=204d03c803de6a656f8adba7f198383ee3751318
---

 configure | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/configure b/configure
index 708ecd9025..ce027d3845 100755
--- a/configure
+++ b/configure
@@ -5130,10 +5130,9 @@ probe_cc(){
     elif $_cc -nologo- 2>&1 | grep -q ^Microsoft || { $_cc -v 2>&1 | grep -q clang && $_cc -? > /dev/null 2>&1; }; then
         _type=msvc
         if $_cc -nologo- 2>&1 | grep -q ^Microsoft; then
-            # The version number is printed on the first line on stderr, stdout
-            # gets the usage instructions. Only include stderr, to avoid
-            # potential ordering race conditions.
-            _ident=$($_cc 2>&1 >/dev/null | head -n1 | tr -d '\r')
+            # Depending on the tool (cl.exe or link.exe), the version number
+            # is printed on the first line of stderr or stdout
+            _ident=$($_cc 2>&1 | grep ^Microsoft | head -n1 | tr -d '\r')
         else
             _ident=$($_cc --version 2>/dev/null | head -n1 | tr -d '\r')
         fi