diff --git a/src/spicelib/analysis/cktdisto.c b/src/spicelib/analysis/cktdisto.c
index 334c15ac9..252554aa2 100644
--- a/src/spicelib/analysis/cktdisto.c
+++ b/src/spicelib/analysis/cktdisto.c
@@ -27,6 +27,8 @@ CKTdisto (CKTcircuit *ckt, int mode)
     int error=0;
     int size;
 
+    /* FALLTHROUGH added to suppress GCC warning due to
+     * -Wimplicit-fallthrough flag */
     switch(mode) {
 
     case D_SETUP:
@@ -63,7 +65,7 @@ CKTdisto (CKTcircuit *ckt, int mode)
     case D_RHSF1:
 
  	   job->Df2given = 0; /* will change if any F2 source is found */
-
+        /* FALLTHROUGH */
     case D_RHSF2:
 
 
diff --git a/src/spicelib/parser/inpptree.c b/src/spicelib/parser/inpptree.c
index 4d2725837..dbae3e913 100644
--- a/src/spicelib/parser/inpptree.c
+++ b/src/spicelib/parser/inpptree.c
@@ -1477,6 +1477,8 @@ void free_tree(INPparseNode *pt)
         controlled_exit(1);
     }
 
+    /* FALLTHROUGH added to suppress GCC warning due to
+     * -Wimplicit-fallthrough flag */
     switch (pt->type) {
     case PT_TIME:
     case PT_TEMPERATURE:
@@ -1493,6 +1495,7 @@ void free_tree(INPparseNode *pt)
     case PT_COMMA:
     case PT_TERN:
         dec_usage(pt->right);
+        /* FALLTHROUGH */
     case PT_FUNCTION:
         dec_usage(pt->left);
         break;