From d11d7849f7676eb8b2c771356b9be8d8bb756cc8 Mon Sep 17 00:00:00 2001
From: Jacek Galowicz <jacek@galowicz.de>
Date: Thu, 2 Nov 2023 15:51:47 +0100
Subject: [PATCH] Use ChildWrapperFunction type and make casts more explicit

---
 src/libutil/processes.cc | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/libutil/processes.cc b/src/libutil/processes.cc
index e1e60302b..28f1adcf0 100644
--- a/src/libutil/processes.cc
+++ b/src/libutil/processes.cc
@@ -168,11 +168,12 @@ void killUser(uid_t uid)
 
 //////////////////////////////////////////////////////////////////////
 
+using ChildWrapperFunction = std::function<void()>;
 
 /* Wrapper around vfork to prevent the child process from clobbering
    the caller's stack frame in the parent. */
-static pid_t doFork(bool allowVfork, std::function<void()> fun) __attribute__((noinline));
-static pid_t doFork(bool allowVfork, std::function<void()> fun)
+static pid_t doFork(bool allowVfork, ChildWrapperFunction & fun) __attribute__((noinline));
+static pid_t doFork(bool allowVfork, ChildWrapperFunction & fun)
 {
 #ifdef __linux__
     pid_t pid = allowVfork ? vfork() : fork();
@@ -188,8 +189,8 @@ static pid_t doFork(bool allowVfork, std::function<void()> fun)
 #if __linux__
 static int childEntry(void * arg)
 {
-    auto main = (std::function<void()> *) arg;
-    (*main)();
+    auto & fun = *reinterpret_cast<ChildWrapperFunction*>(arg);
+    fun();
     return 1;
 }
 #endif