From 5f548a4b6ccc51f613883e8fbb214295f1b8b719 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Sun, 18 Jul 2021 10:31:52 +0200
Subject: [PATCH] misra; implement rule 8.9

---
 addons/misra.py                | 23 +++++++++++++++++++++++
 addons/test/misra/misra-test.c |  3 +++
 2 files changed, 26 insertions(+)

diff --git a/addons/misra.py b/addons/misra.py
index 66cf2a507..764c2e8ef 100755
--- a/addons/misra.py
+++ b/addons/misra.py
@@ -1858,6 +1858,28 @@ class MisraChecker:
             if static_var and extern_var:
                 self.reportError(extern_var.nameToken, 8, 8)
 
+    def misra_8_9(self, cfg):
+        variables = {}
+        for scope in cfg.scopes:
+            if scope.type != 'Function':
+                continue
+            variables_used_in_scope = []
+            tok = scope.bodyStart
+            while tok != scope.bodyEnd:
+                if tok.variable and tok.variable.access == 'Global' and tok.variable.isStatic:
+                    if tok.variable not in variables_used_in_scope:
+                        variables_used_in_scope.append(tok.variable)
+                tok = tok.next
+            for var in variables_used_in_scope:
+                if var in variables:
+                    variables[var] += 1
+                else:
+                    variables[var] = 1
+        for var, count in variables.items():
+            if count == 1:
+                self.reportError(var.nameToken, 8, 9)
+
+
     def misra_8_11(self, data):
         for var in data.variables:
             if var.isExtern and simpleMatch(var.nameToken.next, '[ ]') and var.nameToken.scope.type == 'Global':
@@ -3579,6 +3601,7 @@ class MisraChecker:
             self.executeCheck(806, self.misra_8_6, dumpfile, cfg)
             self.executeCheck(807, self.misra_8_7, dumpfile, cfg)
             self.executeCheck(808, self.misra_8_8, cfg)
+            self.executeCheck(809, self.misra_8_9, cfg)
             self.executeCheck(811, self.misra_8_11, cfg)
             self.executeCheck(812, self.misra_8_12, cfg)
             if cfgNumber == 0:
diff --git a/addons/test/misra/misra-test.c b/addons/test/misra/misra-test.c
index 874cfbbf7..646f88b81 100644
--- a/addons/test/misra/misra-test.c
+++ b/addons/test/misra/misra-test.c
@@ -376,6 +376,9 @@ extern int16_t misra_8_4_count; // 8.4
 static int32_t misra_8_8 = 123;
 extern int32_t misra_8_8; // 8.8 8.4
 
+static int32_t misra_8_9_i; // 8.9
+static int32_t misra_8_9_foo(void) { return misra_8_9_i++; }
+
 extern int a811[]; // 8.11 8.4
 
 enum misra_8_12_a { misra_a1 = 1, misra_a2 = 2, misra_a3, misra_a4 = 3 }; //8.12