diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c
index da4aadbc590..cb92710f2bc 100644
--- a/gcc/c-family/c-common.c
+++ b/gcc/c-family/c-common.c
@@ -8601,8 +8601,8 @@ try_to_locate_new_include_insertion_point (const char *file, location_t loc)
 
   /*  Get ordinary map containing LOC (or its expansion).  */
   const line_map_ordinary *ord_map_for_loc = NULL;
-  loc = linemap_resolve_location (line_table, loc, LRK_MACRO_EXPANSION_POINT,
-				  &ord_map_for_loc);
+  linemap_resolve_location (line_table, loc, LRK_MACRO_EXPANSION_POINT,
+			    &ord_map_for_loc);
   gcc_assert (ord_map_for_loc);
 
   for (unsigned int i = 0; i < LINEMAPS_ORDINARY_USED (line_table); i++)
diff --git a/gcc/config/i386/i386-expand.c b/gcc/config/i386/i386-expand.c
index d50b811d863..1bd251ea8e2 100644
--- a/gcc/config/i386/i386-expand.c
+++ b/gcc/config/i386/i386-expand.c
@@ -19780,8 +19780,7 @@ ix86_expand_sse2_mulvxdi3 (rtx op0, rtx op1, rtx op2)
       emit_insn (gen_vec_widen_umult_even_v4si (t5, 
 					gen_lowpart (V4SImode, op1),
 					gen_lowpart (V4SImode, op2)));
-      op0 = expand_binop (mode, add_optab, t5, t4, op0, 1, OPTAB_DIRECT);
-
+      expand_binop (mode, add_optab, t5, t4, op0, 1, OPTAB_DIRECT);
     }
   else
     {
diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index e4923f4ccbf..07093255505 100644
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -6167,7 +6167,7 @@ build_new_op_1 (const op_location_t &loc, enum tree_code code, int flags,
 	      conv = cand->convs[2];
 	      if (conv->kind == ck_ref_bind)
 		conv = next_conversion (conv);
-	      arg3 = convert_like (conv, arg3, complain);
+	      convert_like (conv, arg3, complain);
 	    }
 
 	}
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index dd76ebe3dbf..77095953134 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -5218,7 +5218,6 @@ cp_build_binary_op (const op_location_t &location,
 	    }
 	  result_type = build_opaque_vector_type (intt,
 						  TYPE_VECTOR_SUBPARTS (type0));
-	  converted = 1;
 	  return build_vec_cmp (resultcode, result_type, op0, op1);
 	}
       build_type = boolean_type_node;
diff --git a/gcc/fortran/check.c b/gcc/fortran/check.c
index a04f0d66655..95801804022 100644
--- a/gcc/fortran/check.c
+++ b/gcc/fortran/check.c
@@ -4884,17 +4884,13 @@ gfc_check_c_funloc (gfc_expr *x)
 
   if (attr.function && !attr.proc_pointer && x->expr_type == EXPR_VARIABLE
       && x->symtree->n.sym == x->symtree->n.sym->result)
-    {
-      gfc_namespace *ns = gfc_current_ns;
-
-      for (ns = gfc_current_ns; ns; ns = ns->parent)
-	if (x->symtree->n.sym == ns->proc_name)
-	  {
-	    gfc_error ("Function result %qs at %L is invalid as X argument "
-		       "to C_FUNLOC", x->symtree->n.sym->name, &x->where);
-	    return false;
-	  }
-    }
+    for (gfc_namespace *ns = gfc_current_ns; ns; ns = ns->parent)
+      if (x->symtree->n.sym == ns->proc_name)
+	{
+	  gfc_error ("Function result %qs at %L is invalid as X argument "
+		     "to C_FUNLOC", x->symtree->n.sym->name, &x->where);
+	  return false;
+	}
 
   if (attr.flavor != FL_PROCEDURE)
     {
diff --git a/gcc/fortran/decl.c b/gcc/fortran/decl.c
index 7e4e8a29984..3d29091282e 100644
--- a/gcc/fortran/decl.c
+++ b/gcc/fortran/decl.c
@@ -2455,7 +2455,6 @@ variable_decl (int elem)
 
       /* %FILL components are given invalid fortran names.  */
       snprintf (name, GFC_MAX_SYMBOL_LEN + 1, "%%FILL%u", fill_id++);
-      m = MATCH_YES;
     }
 
   var_locus = gfc_current_locus;
diff --git a/gcc/fortran/resolve.c b/gcc/fortran/resolve.c
index af7078a46d9..c82e8f21341 100644
--- a/gcc/fortran/resolve.c
+++ b/gcc/fortran/resolve.c
@@ -6573,7 +6573,6 @@ resolve_typebound_function (gfc_expr* e)
     }
 
   c = gfc_find_component (declared, "_data", true, true, NULL);
-  declared = c->ts.u.derived;
 
   /* Treat the call as if it is a typebound procedure, in order to roll
      out the correct name for the specific function.  */
diff --git a/gcc/fortran/simplify.c b/gcc/fortran/simplify.c
index 6c1f4bd4fce..2d20913ca56 100644
--- a/gcc/fortran/simplify.c
+++ b/gcc/fortran/simplify.c
@@ -4714,7 +4714,7 @@ gfc_simplify_matmul (gfc_expr *matrix_a, gfc_expr *matrix_b)
   else
     gcc_unreachable();
 
-  offset_a = offset_b = 0;
+  offset_b = 0;
   for (col = 0; col < result_columns; ++col)
     {
       offset_a = 0;
@@ -6999,20 +6999,17 @@ gfc_simplify_scan (gfc_expr *e, gfc_expr *c, gfc_expr *b, gfc_expr *kind)
 	    indx = 0;
 	}
       else
-	{
-	  i = 0;
-	  for (indx = len; indx > 0; indx--)
-	    {
-	      for (i = 0; i < lenc; i++)
-		{
-		  if (c->value.character.string[i]
-		      == e->value.character.string[indx - 1])
-		    break;
-		}
-	      if (i < lenc)
-		break;
-	    }
-	}
+	for (indx = len; indx > 0; indx--)
+	  {
+	    for (i = 0; i < lenc; i++)
+	      {
+		if (c->value.character.string[i]
+		    == e->value.character.string[indx - 1])
+		  break;
+	      }
+	    if (i < lenc)
+	      break;
+	  }
     }
 
   result = gfc_get_int_expr (k, &e->where, indx);
diff --git a/gcc/fortran/trans-array.c b/gcc/fortran/trans-array.c
index 56d534d0444..1ab03615fda 100644
--- a/gcc/fortran/trans-array.c
+++ b/gcc/fortran/trans-array.c
@@ -4794,8 +4794,6 @@ gfc_could_be_alias (gfc_ss * lss, gfc_ss * rss)
 
   lsym_pointer = lsym->attr.pointer;
   lsym_target = lsym->attr.target;
-  lsym_pointer = lsym->attr.pointer;
-  lsym_target = lsym->attr.target;
 
   for (rref = rexpr->ref; rref != rss->info->data.array.ref; rref = rref->next)
     {
diff --git a/gcc/fortran/trans-common.c b/gcc/fortran/trans-common.c
index debdbd98ac0..9fc23ff5e7c 100644
--- a/gcc/fortran/trans-common.c
+++ b/gcc/fortran/trans-common.c
@@ -1007,10 +1007,8 @@ static void
 add_equivalences (bool *saw_equiv)
 {
   segment_info *f;
-  bool seen_one, more;
+  bool more = TRUE;
 
-  seen_one = false;
-  more = TRUE;
   while (more)
     {
       more = FALSE;
@@ -1019,7 +1017,7 @@ add_equivalences (bool *saw_equiv)
 	  if (!f->sym->equiv_built)
 	    {
 	      f->sym->equiv_built = 1;
-	      seen_one = find_equivalence (f);
+	      bool seen_one = find_equivalence (f);
 	      if (seen_one)
 		{
 		  *saw_equiv = true;
diff --git a/gcc/fortran/trans-expr.c b/gcc/fortran/trans-expr.c
index 074568ab596..a4e8351110a 100644
--- a/gcc/fortran/trans-expr.c
+++ b/gcc/fortran/trans-expr.c
@@ -8912,7 +8912,6 @@ trans_class_vptr_len_assignment (stmtblock_t *block, gfc_expr * le,
 		from_len = rse->string_length;
 	      else if (re->ts.type == BT_CHARACTER && re->ts.u.cl->length)
 		{
-		  from_len = gfc_get_expr_charlen (re);
 		  gfc_init_se (&se, NULL);
 		  gfc_conv_expr (&se, re->ts.u.cl->length);
 		  gfc_add_block_to_block (block, &se.pre);
@@ -10171,10 +10170,6 @@ gfc_trans_array_constructor_copy (gfc_expr * expr1, gfc_expr * expr2)
   stype = gfc_typenode_for_spec (&expr2->ts);
   src = gfc_build_constant_array_constructor (expr2, stype);
 
-  stype = TREE_TYPE (src);
-  if (POINTER_TYPE_P (stype))
-    stype = TREE_TYPE (stype);
-
   return gfc_build_memcpy_call (dst, src, len);
 }
 
@@ -10924,7 +10919,6 @@ gfc_trans_assignment_1 (gfc_expr * expr1, gfc_expr * expr2, bool init_flag,
 		       && (gfc_is_class_array_function (expr2)
 			   || gfc_is_alloc_class_scalar_function (expr2)))
     {
-      tmp = rse.expr;
       tmp = gfc_nullify_alloc_comp (expr1->ts.u.derived, rse.expr, 0);
       gfc_prepend_expr_to_block (&rse.post, tmp);
       if (lss != gfc_ss_terminator && rss == gfc_ss_terminator)
diff --git a/gcc/fortran/trans-intrinsic.c b/gcc/fortran/trans-intrinsic.c
index cc041f9eea7..a7ebc413d6e 100644
--- a/gcc/fortran/trans-intrinsic.c
+++ b/gcc/fortran/trans-intrinsic.c
@@ -10971,7 +10971,6 @@ conv_intrinsic_atomic_op (gfc_code *code)
   fn = (built_in_function) ((int) fn
 			    + exact_log2 (tree_to_uhwi (TYPE_SIZE_UNIT (tmp)))
 			    + 1);
-  tmp = builtin_decl_explicit (fn);
   tree itype = TREE_TYPE (TREE_TYPE (atom));
   tmp = builtin_decl_explicit (fn);
 
diff --git a/gcc/fortran/trans-openmp.c b/gcc/fortran/trans-openmp.c
index 394cbc2a929..8eae7bc0a52 100644
--- a/gcc/fortran/trans-openmp.c
+++ b/gcc/fortran/trans-openmp.c
@@ -1199,7 +1199,6 @@ gfc_omp_finish_clause (tree c, gimple_seq *pre_p)
     {
       OMP_CLAUSE_CHAIN (c4) = OMP_CLAUSE_CHAIN (last);
       OMP_CLAUSE_CHAIN (last) = c4;
-      last = c4;
     }
 }
 
diff --git a/gcc/fortran/trans-types.c b/gcc/fortran/trans-types.c
index 1dbb842a1c4..e1033b3b223 100644
--- a/gcc/fortran/trans-types.c
+++ b/gcc/fortran/trans-types.c
@@ -1817,11 +1817,11 @@ gfc_get_array_descriptor_base (int dimen, int codimen, bool restricted)
   TYPE_NAMELESS (fat_type) = 1;
 
   /* Add the data member as the first element of the descriptor.  */
-  decl = gfc_add_field_to_struct_1 (fat_type,
-				    get_identifier ("data"),
-				    (restricted
-				     ? prvoid_type_node
-				     : ptr_type_node), &chain);
+  gfc_add_field_to_struct_1 (fat_type,
+			     get_identifier ("data"),
+			     (restricted
+			      ? prvoid_type_node
+			      : ptr_type_node), &chain);
 
   /* Add the base component.  */
   decl = gfc_add_field_to_struct_1 (fat_type,
diff --git a/gcc/fortran/trans.c b/gcc/fortran/trans.c
index 0d786d9cf99..303abd994c5 100644
--- a/gcc/fortran/trans.c
+++ b/gcc/fortran/trans.c
@@ -1014,9 +1014,6 @@ gfc_build_final_call (gfc_typespec ts, gfc_expr *final_wrapper, gfc_expr *var,
 	  gfc_add_block_to_block (&block, &se.pre);
 	  gcc_assert (se.post.head == NULL_TREE);
 	  array = se.expr;
-	  if (TREE_CODE (array) == ADDR_EXPR
-	      && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (array, 0))))
-	    tmp = TREE_OPERAND (array, 0);
 
 	  if (!gfc_is_coarray (array_expr))
 	    {
diff --git a/gcc/lra-eliminations.c b/gcc/lra-eliminations.c
index f344e127cfe..051839a2717 100644
--- a/gcc/lra-eliminations.c
+++ b/gcc/lra-eliminations.c
@@ -1053,7 +1053,7 @@ eliminate_regs_in_insn (rtx_insn *insn, bool replace_p, bool first_p,
      PARALLEL since the new one still will, but we can't call
      single_set without having put new body into the insn and the
      re-recognition won't hurt in this rare case.  */
-  id = lra_update_insn_recog_data (insn);
+  lra_update_insn_recog_data (insn);
 }
 
 /* Spill pseudos which are assigned to hard registers in SET.  Add
diff --git a/gcc/reg-stack.c b/gcc/reg-stack.c
index 8c934aaf936..5576630c8f2 100644
--- a/gcc/reg-stack.c
+++ b/gcc/reg-stack.c
@@ -484,7 +484,6 @@ check_asm_stack_operands (rtx_insn *insn)
 
   if (which_alternative < 0)
     {
-      malformed_asm = 1;
       /* Avoid further trouble with this insn.  */
       PATTERN (insn) = gen_rtx_USE (VOIDmode, const0_rtx);
       return 0;
diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index 07791519c6c..29688d2618d 100644
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -5955,7 +5955,6 @@ create_function_info_for (tree decl, const char *name, bool add_id,
 
       gcc_assert (prev_vi->offset < argvi->offset);
       prev_vi->next = argvi->id;
-      prev_vi = argvi;
     }
 
   return vi;
diff --git a/gcc/tree-vect-generic.c b/gcc/tree-vect-generic.c
index 4a53fc44584..8389f5555e8 100644
--- a/gcc/tree-vect-generic.c
+++ b/gcc/tree-vect-generic.c
@@ -1981,7 +1981,6 @@ expand_vector_operations_1 (gimple_stmt_iterator *gsi)
       || code == VEC_UNPACK_FLOAT_LO_EXPR
       || code == VEC_PACK_FLOAT_EXPR)
     {
-      type = TREE_TYPE (rhs1);
       /* We do not know how to scalarize those.  */
       return;
     }
@@ -2004,7 +2003,6 @@ expand_vector_operations_1 (gimple_stmt_iterator *gsi)
       || code == VEC_WIDEN_LSHIFT_HI_EXPR
       || code == VEC_WIDEN_LSHIFT_LO_EXPR)
     {
-      type = TREE_TYPE (rhs1);
       /* We do not know how to scalarize those.  */
       return;
     }
diff --git a/libcpp/line-map.c b/libcpp/line-map.c
index 31439f4aba3..8ab873b4e18 100644
--- a/libcpp/line-map.c
+++ b/libcpp/line-map.c
@@ -1160,8 +1160,7 @@ linemap_get_expansion_filename (struct line_maps *set,
   if (location < RESERVED_LOCATION_COUNT)
     return NULL;
 
-  location =
-    linemap_macro_loc_to_exp_point (set, location, &map);
+  linemap_macro_loc_to_exp_point (set, location, &map);
 
   return LINEMAP_FILE (map);
 }
diff --git a/libcpp/mkdeps.c b/libcpp/mkdeps.c
index 676ae122bde..50f0fb2a80d 100644
--- a/libcpp/mkdeps.c
+++ b/libcpp/mkdeps.c
@@ -378,7 +378,7 @@ make_write (const struct mkdeps *d, FILE *fp, bool phony, unsigned int colmax)
       column = make_write_vec (d->targets, fp, 0, colmax, d->quote_lwm);
       fputs (":", fp);
       column++;
-      column = make_write_vec (d->deps, fp, column, colmax);
+      make_write_vec (d->deps, fp, column, colmax);
       fputs ("\n", fp);
       if (phony)
 	for (unsigned i = 1; i < d->deps.size (); i++)