From 3e2f5d615d3b89a2660fc108b83a266dd2eea820 Mon Sep 17 00:00:00 2001
From: Daniel Bevenius <daniel.bevenius@gmail.com>
Date: Thu, 23 Jan 2020 13:43:03 +0100
Subject: [PATCH] src: ignore GCC -Wcast-function-type for v8.h
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

This commit suggests that cast-function-type warnings be ignored
from v8.h. Currently, GCC reports a number of warnings like this:

In file included from ../src/util.h:27,
                 from ../src/aliased_buffer.h:7,
                 from ../src/memory_tracker.h:5,
                 from ../src/base_object.h:27,
                 from ../src/async_wrap.h:27,
                 from ../src/req_wrap.h:6,
                 from ../src/req_wrap-inl.h:6,
                 from ../src/connect_wrap.h:6,
                 from ../src/connect_wrap.cc:1:
../deps/v8/include/v8.h: In instantiation of
‘void v8::PersistentBase<T>::SetWeak(
    P*,
    typename v8::WeakCallbackInfo<P>::Callback, v8::WeakCallbackType)
[with
P = node::BaseObject;
T = v8::Object;
typename v8::WeakCallbackInfo<P>::Callback =
    void (*)(const v8::WeakCallbackInfo<node::BaseObject>&)]’:

../src/base_object-inl.h:123:42:   required from here
../deps/v8/include/v8.h:10374:16: warning:
cast between incompatible function types from
‘v8::WeakCallbackInfo<node::BaseObject>::Callback’
{aka ‘void (*)(const v8::WeakCallbackInfo<node::BaseObject>&)’} to
‘Callback’
{aka ‘void (*)(const v8::WeakCallbackInfo<void>&)’}
[-Wcast-function-type]
                reinterpret_cast<Callback>(callback), type);
                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The motivation for doing this that it makes it difficult to spot
other warnings that might be important. Since it is v8 that
performs this cast I was not able to find a way around it.
---
 src/base_object-inl.h | 8 ++++++++
 src/node.h            | 7 +++++++
 src/util.h            | 7 +++++++
 3 files changed, 22 insertions(+)

diff --git a/src/base_object-inl.h b/src/base_object-inl.h
index f35cd6734edf0b..3d36eaa923012e 100644
--- a/src/base_object-inl.h
+++ b/src/base_object-inl.h
@@ -27,7 +27,15 @@
 #include "base_object.h"
 #include "env-inl.h"
 #include "util.h"
+
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-function-type"
+#endif
 #include "v8.h"
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic pop
+#endif
 
 namespace node {
 
diff --git a/src/node.h b/src/node.h
index 00b0c0ea7e4541..b615ac8c2138d1 100644
--- a/src/node.h
+++ b/src/node.h
@@ -60,7 +60,14 @@
 # define SIGKILL 9
 #endif
 
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-function-type"
+#endif
 #include "v8.h"  // NOLINT(build/include_order)
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic pop
+#endif
 #include "v8-platform.h"  // NOLINT(build/include_order)
 #include "node_version.h"  // NODE_MODULE_VERSION
 
diff --git a/src/util.h b/src/util.h
index 2f6c17fc321a67..94db8f79c8f166 100644
--- a/src/util.h
+++ b/src/util.h
@@ -24,7 +24,14 @@
 
 #if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
 
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-function-type"
+#endif
 #include "v8.h"
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic pop
+#endif
 
 #include <cassert>
 #include <climits>  // PATH_MAX