bpo-30411: Use --git-dir instead of -C to make git work under version below 1.8.5. (GH-8744)

configure

@@ -781,7 +781,6 @@ infodir
 docdir
 oldincludedir
 includedir
-runstatedir
 localstatedir
 sharedstatedir
 sysconfdir
@@ -891,7 +890,6 @@ datadir='${datarootdir}'
 sysconfdir='${prefix}/etc'
 sharedstatedir='${prefix}/com'
 localstatedir='${prefix}/var'
-runstatedir='${localstatedir}/run'
 includedir='${prefix}/include'
 oldincludedir='/usr/include'
 docdir='${datarootdir}/doc/${PACKAGE_TARNAME}'
@@ -1144,15 +1142,6 @@ do
   | -silent | --silent | --silen | --sile | --sil)
     silent=yes ;;
 
-  -runstatedir | --runstatedir | --runstatedi | --runstated \
-  | --runstate | --runstat | --runsta | --runst | --runs \
-  | --run | --ru | --r)
-    ac_prev=runstatedir ;;
-  -runstatedir=* | --runstatedir=* | --runstatedi=* | --runstated=* \
-  | --runstate=* | --runstat=* | --runsta=* | --runst=* | --runs=* \
-  | --run=* | --ru=* | --r=*)
-    runstatedir=$ac_optarg ;;
-
   -sbindir | --sbindir | --sbindi | --sbind | --sbin | --sbi | --sb)
     ac_prev=sbindir ;;
   -sbindir=* | --sbindir=* | --sbindi=* | --sbind=* | --sbin=* \
@@ -1290,7 +1279,7 @@ fi
 for ac_var in	exec_prefix prefix bindir sbindir libexecdir datarootdir \
 		datadir sysconfdir sharedstatedir localstatedir includedir \
 		oldincludedir docdir infodir htmldir dvidir pdfdir psdir \
-		libdir localedir mandir runstatedir
+		libdir localedir mandir
 do
   eval ac_val=\$$ac_var
   # Remove trailing slashes.
@@ -1443,7 +1432,6 @@ Fine tuning of the installation directories:
   --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
   --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]
   --localstatedir=DIR     modifiable single-machine data [PREFIX/var]
-  --runstatedir=DIR       modifiable per-process data [LOCALSTATEDIR/run]
   --libdir=DIR            object code libraries [EPREFIX/lib]
   --includedir=DIR        C header files [PREFIX/include]
   --oldincludedir=DIR     C header files for non-gcc [/usr/include]
@@ -2757,9 +2745,9 @@ HAS_GIT=no-repository
 fi
 if test $HAS_GIT = found
 then
-    GITVERSION="git -C \$(srcdir) rev-parse --short HEAD"
+    GITVERSION="git --git-dir \$(srcdir)/.git rev-parse --short HEAD"
-    GITTAG="git -C \$(srcdir) describe --all --always --dirty"
+    GITTAG="git --git-dir \$(srcdir)/.git describe --all --always --dirty"
-    GITBRANCH="git -C \$(srcdir) name-rev --name-only HEAD"
+    GITBRANCH="git --git-dir \$(srcdir)/.git name-rev --name-only HEAD"
 else
     GITVERSION=""
     GITTAG=""

configure.ac

@@ -39,9 +39,9 @@ HAS_GIT=no-repository
 fi
 if test $HAS_GIT = found
 then
-    GITVERSION="git -C \$(srcdir) rev-parse --short HEAD"
+    GITVERSION="git --git-dir \$(srcdir)/.git rev-parse --short HEAD"
-    GITTAG="git -C \$(srcdir) describe --all --always --dirty"
+    GITTAG="git --git-dir \$(srcdir)/.git describe --all --always --dirty"
-    GITBRANCH="git -C \$(srcdir) name-rev --name-only HEAD"
+    GITBRANCH="git --git-dir \$(srcdir)/.git name-rev --name-only HEAD"
 else
     GITVERSION=""
     GITTAG=""