According to what I was told by the gcc and glibc people leading whitespace in preprocessor directives is allowed by more recent C/C++ specs. Consequently makedepend should cease to give this warning. diff -ur -N XOrg-6.8.2.orig/xc/config/makedepend/main.c XOrg-6.8.2/xc/config/makedepend/main.c --- XOrg-6.8.2.orig/xc/config/makedepend/main.c 2004-04-23 20:42:00.000000000 +0200 +++ XOrg-6.8.2/xc/config/makedepend/main.c 2005-03-22 13:50:24.000000000 +0100 @@ -709,10 +709,6 @@ if (*bol != '#') bol = NULL; done: - if (bol && whitespace) { - warning("%s: non-portable whitespace encountered at line %d\n", - filep->f_name, lineno); - } filep->f_p = p; filep->f_line = lineno; #ifdef DEBUG_DUMP