-# Optional debuginfo feature (enabled by default)
-AS_IF([test "x$DEFAULT_ENABLE_DEBUGINFO" = xyes],
- [AC_ARG_ENABLE([debug-info], [AC_HELP_STRING([--disable-debug-info], [disable the debug-info feature (default on OS X and Solaris)])], [], [enable_debuginfo=yes])],
- [AC_ARG_ENABLE([debug-info], [AC_HELP_STRING([--enable-debug-info], [enable the debug-info feature (default on Linux)])], [], [enable_debuginfo=no])]
-)
-
-AM_CONDITIONAL([ENABLE_DEBUGINFO], [test "x$enable_debuginfo" = xyes])
-AS_IF([test "x$enable_debuginfo" = xyes], [
+# Set default enable state for debug info.
+# The _enable_debug_info variable is prepended with an underscore to
+# avoid clashing with the one generated by AC_ARG_ENABLE.
+AS_IF([test "x$DEFAULT_ENABLE_DEBUG_INFO" = xyes], [_enable_debug_info=yes], [_enable_debug_info=no])
+
+# Optional debug info feature
+# Do _not_ indent the help string below (appears in the configure --help
+# output).
+AC_ARG_ENABLE([debug-info],
+[AC_HELP_STRING([--enable-debug-info], [enable the debug info feature (default on Linux)])]
+[AC_HELP_STRING([--disable-debug-info], [disable the debug info feature (default on OS X and Solaris)])],
+ [AS_IF([test "x$enableval" = xyes], [_enable_debug_info=yes], [_enable_debug_info=no])], [])
+
+AM_CONDITIONAL([ENABLE_DEBUG_INFO], [test "x$_enable_debug_info" = xyes])
+AS_IF([test "x$_enable_debug_info" = xyes], [