[vala/0.40] vala: Add missing re-check guards for Do/For/WhileStatement and SwitchLabel

[Rico Tzschichholz <ricotz src gnome org>]

commit 345a04124bf17d353844b2b9abdf57003955edf0
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Tue Oct 23 23:12:06 2018 +0200

    vala: Add missing re-check guards for Do/For/WhileStatement and SwitchLabel

 vala/valadostatement.vala    | 18 ++++++++++++++++--
 vala/valaforstatement.vala   | 12 +++++++++++-
 vala/valaswitchlabel.vala    | 11 ++++++++++-
 vala/valawhilestatement.vala | 12 +++++++++++-
 4 files changed, 48 insertions(+), 5 deletions(-)
---
diff --git a/vala/valadostatement.vala b/vala/valadostatement.vala
index 68e6e9320..4849393e7 100644
--- a/vala/valadostatement.vala
+++ b/vala/valadostatement.vala
@@ -93,6 +93,12 @@ public class Vala.DoStatement : CodeNode, Statement {
        }
 
        public override bool check (CodeContext context) {
+               if (checked) {
+                       return !error;
+               }
+
+               checked = true;
+
                // convert to simple loop
 
                // do not generate variable and if block if condition is always true
@@ -102,7 +108,11 @@ public class Vala.DoStatement : CodeNode, Statement {
                        var parent_block = (Block) parent_node;
                        parent_block.replace_statement (this, loop);
 
-                       return loop.check (context);
+                       if (!loop.check (context)) {
+                               error = true;
+                       }
+
+                       return !error;
                }
 
                var block = new Block (source_reference);
@@ -127,6 +137,10 @@ public class Vala.DoStatement : CodeNode, Statement {
                var parent_block = (Block) parent_node;
                parent_block.replace_statement (this, block);
 
-               return block.check (context);
+               if (!block.check (context)) {
+                       error = true;
+               }
+
+               return !error;
        }
 }
diff --git a/vala/valaforstatement.vala b/vala/valaforstatement.vala
index 037a63979..a93e42c6f 100644
--- a/vala/valaforstatement.vala
+++ b/vala/valaforstatement.vala
@@ -165,6 +165,12 @@ public class Vala.ForStatement : CodeNode, Statement {
        }
 
        public override bool check (CodeContext context) {
+               if (checked) {
+                       return !error;
+               }
+
+               checked = true;
+
                // convert to simple loop
 
                var block = new Block (source_reference);
@@ -206,6 +212,10 @@ public class Vala.ForStatement : CodeNode, Statement {
                var parent_block = (Block) parent_node;
                parent_block.replace_statement (this, block);
 
-               return block.check (context);
+               if (!block.check (context)) {
+                       error = true;
+               }
+
+               return !error;
        }
 }
diff --git a/vala/valaswitchlabel.vala b/vala/valaswitchlabel.vala
index a3a5201db..3a46d7c4b 100644
--- a/vala/valaswitchlabel.vala
+++ b/vala/valaswitchlabel.vala
@@ -79,6 +79,12 @@ public class Vala.SwitchLabel : CodeNode {
        }
        
        public override bool check (CodeContext context) {
+               if (checked) {
+                       return !error;
+               }
+
+               checked = true;
+
                if (expression != null) {
                        var switch_statement = (SwitchStatement) section.parent_node;
 
@@ -95,7 +101,10 @@ public class Vala.SwitchLabel : CodeNode {
                                }
                        }
 
-                       expression.check (context);
+                       if (!expression.check (context)) {
+                               error = true;
+                               return false;
+                       }
 
                        if (!expression.is_constant ()) {
                                error = true;
diff --git a/vala/valawhilestatement.vala b/vala/valawhilestatement.vala
index bec6b35b3..5ebc9349f 100644
--- a/vala/valawhilestatement.vala
+++ b/vala/valawhilestatement.vala
@@ -98,6 +98,12 @@ public class Vala.WhileStatement : CodeNode, Statement {
        }
 
        public override bool check (CodeContext context) {
+               if (checked) {
+                       return !error;
+               }
+
+               checked = true;
+
                // convert to simple loop
 
                if (always_true (condition)) {
@@ -118,7 +124,11 @@ public class Vala.WhileStatement : CodeNode, Statement {
                var parent_block = (Block) parent_node;
                parent_block.replace_statement (this, loop);
 
-               return loop.check (context);
+               if (!loop.check (context)) {
+                       error = true;
+               }
+
+               return !error;
        }
 }