[clang] [C++20] [Modules] Support generating in-class defined function with try-catch body (PR #129212)

[Chuanqi Xu via cfe-commits]

https://github.com/ChuanqiXu9 created https://github.com/llvm/llvm-project/pull/129212


See the example:

```
export module func;
class C {
public:
    void member() try {

    } catch (...) {

    }
};
```

We woudln't generate the definition for `C::member` but we should. Since the function is non-inline in modules.

This turns out to be an oversight in parser to me. Since the try-catch body is relatively rare, so maybe we just forgot it.

>From 8876ef70a08f8547d49b89275a3b1b455221abd0 Mon Sep 17 00:00:00 2001
From: Chuanqi Xu <yedeng.yd at linux.alibaba.com>
Date: Fri, 28 Feb 2025 17:03:49 +0800
Subject: [PATCH] [C++20] [Modules] Support generating in-class defined
 function with try-catch body

See the example:

```
export module func;
class C {
public:
    void member() try {

    } catch (...) {

    }
};
```

We woudln't generate the definition for `C::member` but we should. Since
the function is non-inline in modules.

This turns out to be an oversight in parser to me. Since the try-catch
body is relatively rare, so maybe we just forgot it.
---
 clang/lib/Parse/ParseCXXInlineMethods.cpp |  5 +++++
 clang/test/Modules/try-func-body.cppm     | 13 +++++++++++++
 2 files changed, 18 insertions(+)
 create mode 100644 clang/test/Modules/try-func-body.cppm

diff --git a/clang/lib/Parse/ParseCXXInlineMethods.cpp b/clang/lib/Parse/ParseCXXInlineMethods.cpp
index 6c01af55ef3c4..723ebfa59fc03 100644
--- a/clang/lib/Parse/ParseCXXInlineMethods.cpp
+++ b/clang/lib/Parse/ParseCXXInlineMethods.cpp
@@ -632,6 +632,11 @@ void Parser::ParseLexedMethodDef(LexedMethod &LM) {
 
     if (Tok.is(tok::eof) && Tok.getEofData() == LM.D)
       ConsumeAnyToken();
+
+    if (auto *FD = dyn_cast_or_null<FunctionDecl>(LM.D))
+      if (isa<CXXMethodDecl>(FD) ||
+          FD->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend))
+        Actions.ActOnFinishInlineFunctionDef(FD);
     return;
   }
   if (Tok.is(tok::colon)) {
diff --git a/clang/test/Modules/try-func-body.cppm b/clang/test/Modules/try-func-body.cppm
new file mode 100644
index 0000000000000..379f5e47f4f8e
--- /dev/null
+++ b/clang/test/Modules/try-func-body.cppm
@@ -0,0 +1,13 @@
+// RUN: %clang_cc1 -std=c++20 %s -fexceptions -fcxx-exceptions -emit-llvm -triple %itanium_abi_triple -o - | FileCheck %s
+
+export module func;
+class C {
+public:
+    void member() try {
+
+    } catch (...) {
+
+    }
+};
+
+// CHECK: define {{.*}}@_ZNW4func1C6memberEv