fixdep: Do not record dependency on the source file itself

The dependency is already expressed by the Makefiles, storing it in the
.cmd file breaks build if a .c file is replaced by .S or vice versa,
because the .cmd file contains

foo/bar.o: foo/bar.c ...

foo/bar.c ... :

so the foo/bar.c -> foo/bar.o rule triggers even if there is no
foo/bar.c anymore.

Acked-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michal Marek <mmarek@suse.cz>

diff --git a/scripts/basic/fixdep.c b/scripts/basic/fixdep.c
index c9a16abacab4a40a9dc9feb75c4096efc386b35e..6c94c6ce2925f7a35c4c91631ef500f57945fe14 100644 (file)
--- a/scripts/basic/fixdep.c
+++ b/scripts/basic/fixdep.c
@@ -315,6 +315,7 @@ static void parse_dep_file(void *map, size_t len)
        char *end = m + len;
        char *p;
        char s[PATH_MAX];
+       int first;
 
        p = strchr(m, ':');
        if (!p) {
@@ -327,6 +328,7 @@ static void parse_dep_file(void *map, size_t len)
 
        clear_config();
 
+       first = 1;
        while (m < end) {
                while (m < end && (*m == ' ' || *m == '\\' || *m == '\n'))
                        m++;
@@ -340,9 +342,17 @@ static void parse_dep_file(void *map, size_t len)
                if (strrcmp(s, "include/generated/autoconf.h") &&
                    strrcmp(s, "arch/um/include/uml-config.h") &&
                    strrcmp(s, ".ver")) {
-                       printf("  %s \\\n", s);
+                       /*
+                        * Do not output the first dependency (the
+                        * source file), so that kbuild is not confused
+                        * if a .c file is rewritten into .S or vice
+                        * versa.
+                        */
+                       if (!first)
+                               printf("  %s \\\n", s);
                        do_config_file(s);
                }
+               first = 0;
                m = p + 1;
        }
        printf("\n%s: $(deps_%s)\n\n", target, target);