bpo-46263: Don't use MULTIARCH on FreeBSD (#30410)

Misc/NEWS.d/next/Build/2022-01-05-02-58-10.bpo-46263.xiv8NU.rst

@@ -0,0 +1 @@
+``configure`` no longer sets ``MULTIARCH`` on FreeBSD platforms.

configure

@@ -6091,10 +6091,20 @@ $as_echo "none" >&6; }
 fi
 rm -f conftest.c conftest.out
 
-if test x$PLATFORM_TRIPLET != xdarwin; then
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for multiarch" >&5
+$as_echo_n "checking for multiarch... " >&6; }
+case $ac_sys_system in #(
+  Darwin*) :
+    MULTIARCH="" ;; #(
+  FreeBSD*) :
+    MULTIARCH="" ;; #(
+  *) :
     MULTIARCH=$($CC --print-multiarch 2>/dev/null)
-fi
+ ;;
+esac
 
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $MULTIARCH" >&5
+$as_echo "$MULTIARCH" >&6; }
 
 if test x$PLATFORM_TRIPLET != x && test x$MULTIARCH != x; then
   if test x$PLATFORM_TRIPLET != x$MULTIARCH; then
@@ -6104,6 +6114,7 @@ elif test x$PLATFORM_TRIPLET != x && test x$MULTIARCH = x; then
   MULTIARCH=$PLATFORM_TRIPLET
 fi
 
+
 if test x$MULTIARCH != x; then
   MULTIARCH_CPPFLAGS="-DMULTIARCH=\\\"$MULTIARCH\\\""
 fi

configure.ac

@@ -987,10 +987,14 @@ else
 fi
 rm -f conftest.c conftest.out
 
-if test x$PLATFORM_TRIPLET != xdarwin; then
-  MULTIARCH=$($CC --print-multiarch 2>/dev/null)
-fi
-AC_SUBST(MULTIARCH)
+AC_MSG_CHECKING([for multiarch])
+AS_CASE([$ac_sys_system],
+  [Darwin*], [MULTIARCH=""],
+  [FreeBSD*], [MULTIARCH=""],
+  [MULTIARCH=$($CC --print-multiarch 2>/dev/null)]
+)
+AC_SUBST([MULTIARCH])
+AC_MSG_RESULT([$MULTIARCH])
 
 if test x$PLATFORM_TRIPLET != x && test x$MULTIARCH != x; then
   if test x$PLATFORM_TRIPLET != x$MULTIARCH; then
@@ -1000,6 +1004,7 @@ elif test x$PLATFORM_TRIPLET != x && test x$MULTIARCH = x; then
   MULTIARCH=$PLATFORM_TRIPLET
 fi
 AC_SUBST(PLATFORM_TRIPLET)
+
 if test x$MULTIARCH != x; then
   MULTIARCH_CPPFLAGS="-DMULTIARCH=\\\"$MULTIARCH\\\""
 fi