turn down the logical bitwise confusion warning to not warn

when the RHS of the ||/&& is ever 0 or 1.  This handles a variety of
creative idioms for "true" used in C programs and fixes many false 
positives at the expense of a few false negatives.  This fixes
rdar://8230351.

llvm-svn: 109314

4 files changed, 8 insertions, 8 deletions

diff --git a/clang/test/CodeGenCXX/static-init-2.cpp b/clang/test/CodeGenCXX/static-init-2.cpp
index 7eb4a7d5aa7..65ab3bb1262 100644
--- a/clang/test/CodeGenCXX/static-init-2.cpp
+++ b/clang/test/CodeGenCXX/static-init-2.cpp
@@ -3,4 +3,4 @@
 // Make sure we don't crash generating y; its value is constant, but the
 // initializer has side effects, so EmitConstantExpr should fail.
 int x();
-int y = x() && 0;   // expected-warning {{use of logical && with constant operand}}
+int y = x() && 0;
diff --git a/clang/test/Sema/exprs.c b/clang/test/Sema/exprs.c
index 9d3da908549..56a52bed1bc 100644
--- a/clang/test/Sema/exprs.c
+++ b/clang/test/Sema/exprs.c
@@ -145,5 +145,8 @@ void test19() {
 int test20(int x) {
   return x && 4; // expected-warning {{use of logical && with constant operand; switch to bitwise & or remove constant}}
 
-  return x && sizeof(int) == 4;  // no warning.
+  return x && sizeof(int) == 4;  // no warning, RHS is logical op.
+  
+  // no warning, this is an idiom for "true" in old C style.
+  return x && (signed char)1;
 }
diff --git a/clang/test/Sema/switch.c b/clang/test/Sema/switch.c
index 4e39e0f0c2d..bb4822916cc 100644
--- a/clang/test/Sema/switch.c
+++ b/clang/test/Sema/switch.c
@@ -50,14 +50,12 @@ void test4()
   }
   
   switch (cond) {
-  case g() && 0: // expected-error {{expression is not an integer constant expression}} // expected-note {{subexpression not valid in an integer constant expression}} \
-                    expected-warning {{use of logical && with constant operand}}
+  case g() && 0: // expected-error {{expression is not an integer constant expression}} // expected-note {{subexpression not valid in an integer constant expression}}
     break;
   }
   
   switch (cond) {
-  case 0 ... g() || 1: // expected-error {{expression is not an integer constant expression}} // expected-note {{subexpression not valid in an integer constant expression}} \\
-                          expected-warning {{use of logical || with constant operand}}
+  case 0 ... g() || 1: // expected-error {{expression is not an integer constant expression}} // expected-note {{subexpression not valid in an integer constant expression}}
     break;
   }
 }
diff --git a/clang/test/SemaCXX/switch.cpp b/clang/test/SemaCXX/switch.cpp
index 54240dcc305..fc13630bbf1 100644
--- a/clang/test/SemaCXX/switch.cpp
+++ b/clang/test/SemaCXX/switch.cpp
@@ -8,8 +8,7 @@ void test() {
   }
 
   int n = 3;
-  switch (n && 1) { // expected-warning {{bool}} \
-                    // expected-warning {{use of logical && with constant operand}}
+  switch (n && 1) { // expected-warning {{bool}}
     case 1:
       break;
   }