Modified -Wfloat-equal logic to suppress warnings where floating point values
are compared against builtins such as __builtin_inf.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@44058 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Sema/SemaExpr.cpp b/Sema/SemaExpr.cpp
index a533da6..e87ad6a 100644
--- a/Sema/SemaExpr.cpp
+++ b/Sema/SemaExpr.cpp
@@ -1218,6 +1218,33 @@
return E;
}
+// Utility method to plow through parenthesis and casts.
+static inline Expr* IgnoreParenCasts(Expr* E) {
+ while(true) {
+ if (ParenExpr* P = dyn_cast<ParenExpr>(E))
+ E = P->getSubExpr();
+ else if (CastExpr* P = dyn_cast<CastExpr>(E))
+ E = P->getSubExpr();
+ else if (ImplicitCastExpr* P = dyn_cast<ImplicitCastExpr>(E))
+ E = P->getSubExpr();
+ else
+ break;
+ }
+
+ return E;
+}
+
+// Utility method to determine if a CallExpr is a call to a builtin.
+static inline bool isCallBuiltin(CallExpr* cexp) {
+ Expr* sub = IgnoreParenCasts(cexp->getCallee());
+
+ if (DeclRefExpr* E = dyn_cast<DeclRefExpr>(sub))
+ if (E->getDecl()->getIdentifier()->getBuiltinID() > 0)
+ return true;
+
+ return false;
+}
+
inline QualType Sema::CheckCompareOperands( // C99 6.5.8
Expr *&lex, Expr *&rex, SourceLocation loc, bool isRelational)
{
@@ -1254,11 +1281,27 @@
// Special case: check for x == x (which is OK).
bool EmitWarning = true;
- if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(IgnoreParen(lex)))
- if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(IgnoreParen(rex)))
+ Expr* LeftExprSansParen = IgnoreParen(lex);
+ Expr* RightExprSansParen = IgnoreParen(rex);
+
+ // Look for x == x. Do not emit warnings for such cases.
+ if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LeftExprSansParen))
+ if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RightExprSansParen))
if (DRL->getDecl() == DRR->getDecl())
EmitWarning = false;
+
+ // Check for comparisons with builtin types.
+ if (EmitWarning)
+ if (CallExpr* CL = dyn_cast<CallExpr>(LeftExprSansParen))
+ if (isCallBuiltin(CL))
+ EmitWarning = false;
+ if (EmitWarning)
+ if (CallExpr* CR = dyn_cast<CallExpr>(RightExprSansParen))
+ if (isCallBuiltin(CR))
+ EmitWarning = false;
+
+ // Emit the diagnostic.
if (EmitWarning)
Diag(loc, diag::warn_floatingpoint_eq,
lex->getSourceRange(),rex->getSourceRange());