[clang] 2f71cf6 - [SemaObjC] Fix a -Wobjc-signed-char-bool false-positive with binary conditional operator

[Erik Pilkington via cfe-commits]

Author: Erik Pilkington
Date: 2020-07-07T13:29:54-04:00
New Revision: 2f71cf6d77c5cc679968851080d0513d84ddccb6

URL: https://github.com/llvm/llvm-project/commit/2f71cf6d77c5cc679968851080d0513d84ddccb6
DIFF: https://github.com/llvm/llvm-project/commit/2f71cf6d77c5cc679968851080d0513d84ddccb6.diff

LOG: [SemaObjC] Fix a -Wobjc-signed-char-bool false-positive with binary conditional operator

We were previously bypassing the conditional expression special case for binary
conditional expressions.

rdar://64134411

Differential revision: https://reviews.llvm.org/D81751

Added: 
    

Modified: 
    clang/lib/Sema/SemaChecking.cpp
    clang/test/SemaObjC/signed-char-bool-conversion.m

Removed: 
    


################################################################################
diff  --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index 2b52415b2800..77858b17d62c 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -11936,27 +11936,31 @@ static void CheckImplicitConversion(Sema &S, Expr *E, QualType T,
       }
 }
 
-static void CheckConditionalOperator(Sema &S, ConditionalOperator *E,
+static void CheckConditionalOperator(Sema &S, AbstractConditionalOperator *E,
                                      SourceLocation CC, QualType T);
 
 static void CheckConditionalOperand(Sema &S, Expr *E, QualType T,
                                     SourceLocation CC, bool &ICContext) {
   E = E->IgnoreParenImpCasts();
 
-  if (isa<ConditionalOperator>(E))
-    return CheckConditionalOperator(S, cast<ConditionalOperator>(E), CC, T);
+  if (auto *CO = dyn_cast<AbstractConditionalOperator>(E))
+    return CheckConditionalOperator(S, CO, CC, T);
 
   AnalyzeImplicitConversions(S, E, CC);
   if (E->getType() != T)
     return CheckImplicitConversion(S, E, T, CC, &ICContext);
 }
 
-static void CheckConditionalOperator(Sema &S, ConditionalOperator *E,
+static void CheckConditionalOperator(Sema &S, AbstractConditionalOperator *E,
                                      SourceLocation CC, QualType T) {
   AnalyzeImplicitConversions(S, E->getCond(), E->getQuestionLoc());
 
+  Expr *TrueExpr = E->getTrueExpr();
+  if (auto *BCO = dyn_cast<BinaryConditionalOperator>(E))
+    TrueExpr = BCO->getCommon();
+
   bool Suspicious = false;
-  CheckConditionalOperand(S, E->getTrueExpr(), T, CC, Suspicious);
+  CheckConditionalOperand(S, TrueExpr, T, CC, Suspicious);
   CheckConditionalOperand(S, E->getFalseExpr(), T, CC, Suspicious);
 
   if (T->isBooleanType())
@@ -11975,7 +11979,7 @@ static void CheckConditionalOperator(Sema &S, ConditionalOperator *E,
   if (E->getType() == T) return;
 
   Suspicious = false;
-  CheckImplicitConversion(S, E->getTrueExpr()->IgnoreParenImpCasts(),
+  CheckImplicitConversion(S, TrueExpr->IgnoreParenImpCasts(),
                           E->getType(), CC, &Suspicious);
   if (!Suspicious)
     CheckImplicitConversion(S, E->getFalseExpr()->IgnoreParenImpCasts(),
@@ -12038,7 +12042,7 @@ static void AnalyzeImplicitConversions(
 
   // For conditional operators, we analyze the arguments as if they
   // were being fed directly into the output.
-  if (auto *CO = dyn_cast<ConditionalOperator>(SourceExpr)) {
+  if (auto *CO = dyn_cast<AbstractConditionalOperator>(SourceExpr)) {
     CheckConditionalOperator(S, CO, CC, T);
     return;
   }

diff  --git a/clang/test/SemaObjC/signed-char-bool-conversion.m b/clang/test/SemaObjC/signed-char-bool-conversion.m
index 183f60fafcd5..9442d8fa86a9 100644
--- a/clang/test/SemaObjC/signed-char-bool-conversion.m
+++ b/clang/test/SemaObjC/signed-char-bool-conversion.m
@@ -108,3 +108,15 @@ int main() {
   f<short>(); // expected-note {{in instantiation of function template specialization 'f<short>' requested here}}
 }
 #endif
+
+void t5(BOOL b) {
+  int i;
+  b = b ?: YES; // no warning
+  b = b ?: i; // expected-warning {{implicit conversion from integral type 'int' to 'BOOL'}}
+  b = (b = i) // expected-warning {{implicit conversion from integral type 'int' to 'BOOL'}}
+               ?: YES;
+  b = (1 ? YES : i) ?: YES; // expected-warning {{implicit conversion from integral type 'int' to 'BOOL'}}
+  b = b ?: (1 ? i : i); // expected-warning 2 {{implicit conversion from integral type 'int' to 'BOOL'}}
+
+  b = b ? YES : (i ?: 0); // expected-warning {{implicit conversion from integral type 'int' to 'BOOL'}}
+}