build: default to --enable-gcc-warnings for git tree

Anyone developing on coreutils can be assumed to have a new enough
environment, such that enabling gcc warnings by default will be
useful.  Tarballs still default to no warnings, and the defaults
can still be overridden with --disable-gcc-warnings.

* configure.ac (gl_gcc_warnings): Set default based on environment.
Suggested by Bernhard Voelker.

diff --git a/configure.ac b/configure.ac
index d087c33b50af845df7ebd9cb8b7f0d600777f98d..e1aa6caf1cd673c6f10f5633939afa623e5199f2 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -75,7 +75,11 @@ AC_ARG_ENABLE([gcc-warnings],
      *)      AC_MSG_ERROR([bad value $enableval for gcc-warnings option]) ;;
    esac
    gl_gcc_warnings=$enableval],
-  [gl_gcc_warnings=no]
+  [if test -d "$srcdir"/.git; then
+     gl_gcc_warnings=yes
+   else
+     gl_gcc_warnings=no
+   fi]
 )
 
 # gl_GCC_VERSION_IFELSE([major], [minor], [run-if-found], [run-if-not-found])