diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index d627749de61..4bdd444cf07 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,14 @@
+2018-05-04  Tom Tromey  <tom@tromey.com>
+
+	* riscv-tdep.c (riscv_isa_xlen): Add fall-through comment.
+	* utils.c (can_dump_core) <LIMIT_CUR>: Add fall-through comment.
+	* eval.c (fetch_subexp_value) <MEMORY_ERROR>: Add fall-through
+	comment.
+	* d-valprint.c (d_val_print) <TYPE_CODE_STRUCT>: Add fall-through
+	comment.
+	* coffread.c (coff_symtab_read) <C_LABEL>: Add fall-through
+	comment.
+
 2018-05-04  Tom Tromey  <tom@tromey.com>
 
 	* dwarf2loc.c (unimplemented): Add ATTRIBUTE_NORETURN.
diff --git a/gdb/coffread.c b/gdb/coffread.c
index 192d38c331e..f24ec0713a0 100644
--- a/gdb/coffread.c
+++ b/gdb/coffread.c
@@ -928,6 +928,7 @@ coff_symtab_read (minimal_symbol_reader &reader,
 	     backtraces, so filter them out (from phdm@macqel.be).  */
 	  if (within_function)
 	    break;
+	  /* Fall through.  */
 	case C_STAT:
 	case C_THUMBLABEL:
 	case C_THUMBSTAT:
diff --git a/gdb/d-valprint.c b/gdb/d-valprint.c
index e2d84313627..579d3c8c916 100644
--- a/gdb/d-valprint.c
+++ b/gdb/d-valprint.c
@@ -88,6 +88,7 @@ d_val_print (struct type *type, int embedded_offset,
 				  stream, recurse, val, options);
 	if (ret == 0)
 	  break;
+	/* Fall through.  */
       default:
 	c_val_print (type, embedded_offset, address, stream,
 		     recurse, val, options);
diff --git a/gdb/eval.c b/gdb/eval.c
index 806a7023d2c..5bd6e2cbfea 100644
--- a/gdb/eval.c
+++ b/gdb/eval.c
@@ -215,6 +215,7 @@ fetch_subexp_value (struct expression *exp, int *pc, struct value **valp,
 	case MEMORY_ERROR:
 	  if (!preserve_errors)
 	    break;
+	  /* Fall through.  */
 	default:
 	  throw_exception (ex);
 	  break;
diff --git a/gdb/riscv-tdep.c b/gdb/riscv-tdep.c
index 149e5e3cec9..9fa458b79b5 100644
--- a/gdb/riscv-tdep.c
+++ b/gdb/riscv-tdep.c
@@ -369,6 +369,7 @@ riscv_isa_xlen (struct gdbarch *gdbarch)
     {
     default:
       warning (_("unknown xlen size, assuming 4 bytes"));
+      /* Fall through.  */
     case 1:
       return 4;
     case 2:
diff --git a/gdb/utils.c b/gdb/utils.c
index e274f026764..63929b2a54c 100644
--- a/gdb/utils.c
+++ b/gdb/utils.c
@@ -275,6 +275,7 @@ can_dump_core (enum resource_limit_kind limit_kind)
     case LIMIT_CUR:
       if (rlim.rlim_cur == 0)
 	return 0;
+      /* Fall through.  */
 
     case LIMIT_MAX:
       if (rlim.rlim_max == 0)