[lldb] Don't emit a warning when using Objective-C getters in expressions
Clang emits a warning when accessing an Objective-C getter but not using the result.
This gets triggered when just trying to print a getter value in the expression parser (where
Clang just sees a normal expression like `obj.getter` while parsing).
This patch just disables the warning in the expression parser (similar to what we do with
the C++ equivalent of just accessing a member variable but not doing anything with it).
Reviewed By: kastiglione
Differential Revision: https://reviews.llvm.org/D94307
GitOrigin-RevId: 19b4d3ce27d5c8ed19bf08cdceb4c03608d2c66d
diff --git a/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp b/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
index 7644a5e..0f3d36c 100644
--- a/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
+++ b/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
@@ -343,6 +343,7 @@
const std::vector<const char *> groupsToIgnore = {
"unused-value",
"odr",
+ "unused-getter-return-value",
};
for (const char *group : groupsToIgnore) {
compiler.getDiagnostics().setSeverityForGroup(
diff --git a/test/API/lang/objc/warnings-in-expr-parser/Makefile b/test/API/lang/objc/warnings-in-expr-parser/Makefile
new file mode 100644
index 0000000..2f74200
--- /dev/null
+++ b/test/API/lang/objc/warnings-in-expr-parser/Makefile
@@ -0,0 +1,5 @@
+OBJC_SOURCES := main.m
+LD_EXTRAS := -framework Foundation
+CFLAGS_EXTRAS := -fobjc-arc
+
+include Makefile.rules
diff --git a/test/API/lang/objc/warnings-in-expr-parser/TestObjCWarningsInExprParser.py b/test/API/lang/objc/warnings-in-expr-parser/TestObjCWarningsInExprParser.py
new file mode 100644
index 0000000..b0b52cb
--- /dev/null
+++ b/test/API/lang/objc/warnings-in-expr-parser/TestObjCWarningsInExprParser.py
@@ -0,0 +1,23 @@
+"""
+Test the warnings that LLDB emits when parsing Objective-C expressions.
+"""
+
+import lldb
+from lldbsuite.test.decorators import *
+from lldbsuite.test.lldbtest import *
+from lldbsuite.test import lldbutil
+
+class TestCase(TestBase):
+
+ mydir = TestBase.compute_mydir(__file__)
+
+ @skipUnlessDarwin
+ @no_debug_info_test
+ def test(self):
+ self.build()
+ lldbutil.run_to_source_breakpoint(self, "// break here", lldb.SBFileSpec("main.m"))
+
+ # Don't warn about not using the result of getters. This is perfectly
+ # fine in the expression parser and LLDB shouldn't warn the user about that.
+ result = self.frame().EvaluateExpression("m.m; unknown_var_to_cause_an_error")
+ self.assertNotIn("getters should not", str(result.GetError()))
diff --git a/test/API/lang/objc/warnings-in-expr-parser/main.m b/test/API/lang/objc/warnings-in-expr-parser/main.m
new file mode 100644
index 0000000..8d71933
--- /dev/null
+++ b/test/API/lang/objc/warnings-in-expr-parser/main.m
@@ -0,0 +1,15 @@
+#include <Foundation/Foundation.h>
+
+@interface MyClass : NSObject
+@property int m;
+@end
+
+@implementation MyClass {
+}
+@end
+
+int main() {
+ MyClass *m = [[MyClass alloc] init];
+ m.m;
+ return 0; // break here
+}
