[clang-repl] Fix Value for platforms where unqualified char is unsigned

[weliveindetail]

Signedness of unqualified char is unspecified and varies between platforms. This patch adds Char_U in REPL_BUILTIN_TYPES to account for platforms that default to unsigned char.

[llvmbot]

@llvm/pr-subscribers-clang

Author: Stefan Gränitz (weliveindetail)

Changes

Signedness of unqualified char is unspecified and varies between platforms. This patch adds Char_U in REPL_BUILTIN_TYPES to account for platforms that default to unsigned char.

---

Full diff: https://github.com/llvm/llvm-project/pull/86118.diff

2 Files Affected:

• (modified) clang/include/clang/Interpreter/Value.h (+1)
• (modified) clang/unittests/Interpreter/InterpreterTest.cpp (+6)

diff --git a/clang/include/clang/Interpreter/Value.h b/clang/include/clang/Interpreter/Value.h
index c380cd91550def..d70e8f8719026b 100644
--- a/clang/include/clang/Interpreter/Value.h
+++ b/clang/include/clang/Interpreter/Value.h
@@ -76,6 +76,7 @@ class QualType;
   X(bool, Bool)                                                                \
   X(char, Char_S)                                                              \
   X(signed char, SChar)                                                        \
+  X(unsigned char, Char_U)                                                     \
   X(unsigned char, UChar)                                                      \
   X(short, Short)                                                              \
   X(unsigned short, UShort)                                                    \
diff --git a/clang/unittests/Interpreter/InterpreterTest.cpp b/clang/unittests/Interpreter/InterpreterTest.cpp
index e76c0677db5ead..4b5d73769e5da7 100644
--- a/clang/unittests/Interpreter/InterpreterTest.cpp
+++ b/clang/unittests/Interpreter/InterpreterTest.cpp
@@ -340,6 +340,12 @@ TEST(InterpreterTest, Value) {
   EXPECT_EQ(V1.getKind(), Value::K_Int);
   EXPECT_FALSE(V1.isManuallyAlloc());
 
+  Value V1b;
+  llvm::cantFail(Interp->ParseAndExecute("char x = 42;"));
+  llvm::cantFail(Interp->ParseAndExecute("c", &V1b));
+  EXPECT_TRUE(V1b.getKind() == Value::K_Char_S ||
+              V1b.getKind() == Value::K_Char_U);
+
   Value V2;
   llvm::cantFail(Interp->ParseAndExecute("double y = 3.14;"));
   llvm::cantFail(Interp->ParseAndExecute("y", &V2));

[vgvassilev]

Good catch! Thank you, @weliveindetail!

[weliveindetail]

Let's give the pre-merge checks a 2nd chance..

[weliveindetail]

Windows buildbot failure is unrelated. This code is covered in unittest ClangReplInterpreterTests and it passed.