# HG changeset patch
# User jbe
# Date 1422564142 -3600
# Node ID 2bdea79e5860434d6c26bd98c3a6149fff2bd8e3
# Parent  78694b82078fe8a349e830e3873b1049b919c173
Use memcpy() instead of dereferencing type-punned pointers to avoid breaking strict-aliasing rules

diff -r 78694b82078f -r 2bdea79e5860 moonbridge.c
--- a/moonbridge.c	Thu Jan 29 21:29:15 2015 +0100
+++ b/moonbridge.c	Thu Jan 29 21:42:22 2015 +0100
@@ -677,7 +677,7 @@
         control_message->cmsg_level = SOL_SOCKET;
         control_message->cmsg_type = SCM_RIGHTS;
         control_message->cmsg_len = CMSG_LEN(sizeof(int));
-        *((int *)CMSG_DATA(control_message)) = fd;
+        memcpy(CMSG_DATA(control_message), &fd, sizeof(int));
       }
     }
     while (sendmsg(worker->controlfd, &message, MSG_NOSIGNAL) < 0) {
@@ -699,7 +699,7 @@
     if (moonbr_debug) {
       moonbr_log(LOG_DEBUG, "Sending memory pointer to child process in pool #%i (PID %i)", (int)status, worker->pool->poolnum, (int)worker->pid);
     }
-    *((intptr_t *)buf) = (intptr_t)ptr;
+    memcpy(buf, &ptr, sizeof(void *));
     while (len) {
       written = send(worker->controlfd, pos, len, MSG_NOSIGNAL);
       if (written > 0) {
@@ -773,7 +773,7 @@
       if (control_message->cmsg_type != SCM_RIGHTS) {
         moonbr_child_log_fatal("Received control message with cmsg_type not equal to SCM_RIGHTS");
       }
-      *fd = *((int *)CMSG_DATA(control_message));
+      memcpy(fd, CMSG_DATA(control_message), sizeof(int));
     } else {
       *fd = -1;
     }
@@ -797,7 +797,11 @@
       moonbr_child_log_errno_fatal("Error while trying to receive memory pointer from parent process");
     }
   }
-  return (void *)*(intptr_t *)buf;
+  {
+    void *ptr;  /* avoid breaking strict-aliasing rules */
+    memcpy(&ptr, buf, sizeof(void *));
+    return ptr;
+  }
 }
 
 /* Throws a Lua error message with an error string for errno appended to it */