From: Richard Trieu <rtrieu@google.com>
Date: Fri, 4 May 2012 03:01:54 +0000 (+0000)
Subject: Skip checking for infinite for-loops if there are global or static variables
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=9087599e5ee64ecd30194b3d89f8748ac95c62f7;p=clang

Skip checking for infinite for-loops if there are global or static variables
in the conditional.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@156148 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp
index 66ddbaabf1..2d03ab99ef 100644
--- a/lib/Sema/SemaStmt.cpp
+++ b/lib/Sema/SemaStmt.cpp
@@ -1214,11 +1214,12 @@ public:
     // No decls found.
     if (Decls.size() == 0) return;
 
-    // Don't warn on volatile decls.
+    // Don't warn on volatile, static, or global variables.
     for (llvm::SmallPtrSet<VarDecl*, 8>::iterator I = Decls.begin(),
                                                   E = Decls.end();
          I != E; ++I)
-      if ((*I)->getType().isVolatileQualified()) return;
+      if ((*I)->getType().isVolatileQualified() ||
+          (*I)->hasGlobalStorage()) return;
 
     if (DeclMatcher(S, Decls, Second).FoundDeclInUse() ||
         DeclMatcher(S, Decls, Third).FoundDeclInUse() ||
diff --git a/test/SemaCXX/warn-loop-analysis.cpp b/test/SemaCXX/warn-loop-analysis.cpp
index a55ca6c6ea..627bc51d1b 100644
--- a/test/SemaCXX/warn-loop-analysis.cpp
+++ b/test/SemaCXX/warn-loop-analysis.cpp
@@ -144,3 +144,11 @@ void test5() {
   for (int a; a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a;);//\
    // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
 }
+
+// Ignore global variables and static variables.
+int x6;
+void test6() {
+  static int y;
+  for (;x6;);
+  for (;y;);
+}