kconfig_lint: Exclude some Kconfig symbols from unused symbol checks

The configuration that coreboot uses for setting selected symbols
typically involves a structure like this:
config BLEH_SPECIFIC_OPTIONS
def_bool y
select SYMBOL

This leads to an an extra kconfig symbol BLEH_SPECIFIC_OPTIONS
that is never referenced by anything else, generating a warning.

Since this is currently the construct that coreboot uses, filter it
out of the warnings for now.

Change-Id: I85a95e4c4e8469870c7f219f2a92955819845573
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/13457
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/util/lint/kconfig_lint b/util/lint/kconfig_lint
index 4315768709..44e898fa40 100755
--- a/util/lint/kconfig_lint
+++ b/util/lint/kconfig_lint
@@ -51,6 +51,8 @@ my %used_symbols;          # structure of symbols used in the tree, and where th
 my @collected_symbols;     #
 my %selected_symbols;      # list of symbols that are enabled by a select statement
 
+my $exclude_unused = '_SPECIFIC_OPTIONS|SOUTH_BRIDGE_OPTIONS';
+
 Main();
 
 #-------------------------------------------------------------------------------
@@ -380,6 +382,10 @@ sub check_used_symbols {
     # loop through all defined symbols and see if they're used anywhere
     foreach my $key ( sort ( keys %symbols ) ) {
 
+        if ( $key =~ /$exclude_unused/ ) {
+            next;
+        }
+
         #see if they're used internal to Kconfig
         next if ( exists $referenced_symbols{$key} );