Add comment why seemingly dead code is necessary

diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
index db584c4e7e4743a8368cc08a5777c8377a66be69..4415efafec08c867d202f7a738ba681797151bd5 100644 (file)
--- a/src/pl/plperl/plperl.c
+++ b/src/pl/plperl/plperl.c
@@ -832,7 +832,15 @@ pp_require_safe(pTHX)
        RETPUSHYES;
 
    DIE(aTHX_ "Unable to load %s into plperl", name);
-   return NULL;                /* keep compiler quiet */
+   /*
+    * In most Perl versions, DIE() expands to a return statement, so the next
+    * line is not necessary.  But in versions between but not including 5.11.1
+    * and 5.13.3 it does not, so the next line is necessary to avoid a
+    * "control reaches end of non-void function" warning from gcc.  Other
+    * compilers such as Solaris Studio will, however, issue a "statement not
+    * reached" warning instead.
+    */
+   return NULL;
 }