[PATCH] D47687: fix: [Bug 18971] - Missing -Wparentheses warning

[eric via Phabricator via cfe-commits]

Higuoxing created this revision.
Herald added a subscriber: cfe-commits.
Higuoxing edited the summary of this revision.

Hi,

As you see, to avoid some expression like

  assert(x || y && "some messages");

clang will skip all the parentheses check if the expression is in `macro`;
and this rule is a little bit loose, if a function which takes boolean variables defined in `macros`,
clang will not check parentheses for these functions;

So, in this patch I add a string type checking, if and only if a function defined in macro and the RHS of boolean expression is a string, then skip the parentheses checking :)

Thanks for reviewing :)


Repository:
  rC Clang

https://reviews.llvm.org/D47687

Files:
  lib/Sema/SemaExpr.cpp


Index: lib/Sema/SemaExpr.cpp
===================================================================
--- lib/Sema/SemaExpr.cpp
+++ lib/Sema/SemaExpr.cpp
@@ -12310,7 +12310,14 @@
 
   // Warn about arg1 || arg2 && arg3, as GCC 4.3+ does.
   // We don't warn for 'assert(a || b && "bad")' since this is safe.
-  if (Opc == BO_LOr && !OpLoc.isMacroID()/* Don't warn in macros. */) {
+  StringLiteral* diagnoseRHSToBeString
+    = dyn_cast<StringLiteral>(RHSExpr->IgnoreImpCasts());
+  if (Opc == BO_LOr && 
+     !(OpLoc.isMacroID() && 
+     diagnoseRHSToBeString)
+    /* Don't warn in macros, 
+       if and only if RHS could be 
+       evaluated as string */) {
     DiagnoseLogicalAndInLogicalOrLHS(Self, OpLoc, LHSExpr, RHSExpr);
     DiagnoseLogicalAndInLogicalOrRHS(Self, OpLoc, LHSExpr, RHSExpr);
   }


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