Merge pull request #11536 from swiftlang/lldb/expr-debug-map-fix-to-21.x

🍒 [lldb][IRExecutionUnit] Return error on failure to resolve function address

Author: Michael137

lldb/source/Expression/IRExecutionUnit.cpp

@@ -789,7 +789,12 @@ ResolveFunctionCallLabel(FunctionCallLabel &label,
   sc_list.Append(*sc_or_err);
 
   LoadAddressResolver resolver(*sc.target_sp, symbol_was_missing_weak);
-  return resolver.Resolve(sc_list).value_or(LLDB_INVALID_ADDRESS);
+  lldb::addr_t resolved_addr =
+      resolver.Resolve(sc_list).value_or(LLDB_INVALID_ADDRESS);
+  if (resolved_addr == LLDB_INVALID_ADDRESS)
+    return llvm::createStringError("couldn't resolve address for function");
+
+  return resolved_addr;
 }
 
 lldb::addr_t

lldb/test/API/lang/cpp/function-call-from-object-file/Makefile

@@ -0,0 +1,3 @@
+CXX_SOURCES := main.cpp lib1.cpp lib2.cpp
+
+include Makefile.rules

lldb/test/API/lang/cpp/function-call-from-object-file/TestFunctionCallFromObjectFile.py

@@ -0,0 +1,29 @@
+"""
+Tests that we can call functions that have definitions in multiple
+CUs in the debug-info (which is the case for functions defined in headers).
+The linker will most likely de-duplicate the functiond definitions when linking
+the final executable. On Darwin, this will create a debug-map that LLDB will use
+to fix up object file addresses to addresses in the linked executable. However,
+if we parsed the DIE from the object file whose functiond definition got stripped
+by the linker, LLDB needs to ensure it can still resolve the function symbol it
+got for it.
+"""
+
+import lldb
+from lldbsuite.test.decorators import *
+from lldbsuite.test.lldbtest import *
+from lldbsuite.test import lldbutil
+
+
+class TestFunctionCallFromObjectFile(TestBase):
+    def test_lib1(self):
+        self.build()
+        lldbutil.run_to_name_breakpoint(self, "lib1_func")
+
+        self.expect_expr("Foo{}.foo()", result_type="int", result_value="15")
+
+    def test_lib2(self):
+        self.build()
+        lldbutil.run_to_name_breakpoint(self, "lib2_func")
+
+        self.expect_expr("Foo{}.foo()", result_type="int", result_value="15")

lldb/test/API/lang/cpp/function-call-from-object-file/common.h

@@ -0,0 +1,8 @@
+#ifndef COMMON_H_IN
+#define COMMON_H_IN
+
+struct Foo {
+  int foo() { return 15; }
+};
+
+#endif // COMMON_H_IN

lldb/test/API/lang/cpp/function-call-from-object-file/lib1.cpp

@@ -0,0 +1,8 @@
+#include "common.h"
+
+// Parameter "Foo*" forces LLDB to parse "Foo" from the object
+// file that it is stopped in.
+void lib1_func(Foo *) {
+  // Force definition into lib1.o debug-info.
+  Foo{}.foo();
+}

lldb/test/API/lang/cpp/function-call-from-object-file/lib2.cpp

@@ -0,0 +1,6 @@
+#include "common.h"
+
+void lib2_func(Foo *) {
+  // Force definition into lib2.o debug-info.
+  Foo{}.foo();
+}

lldb/test/API/lang/cpp/function-call-from-object-file/main.cpp

@@ -0,0 +1,10 @@
+struct Foo;
+
+extern void lib1_func(Foo *);
+extern void lib2_func(Foo *);
+
+int main() {
+  lib1_func(nullptr);
+  lib2_func(nullptr);
+  return 0;
+}