In Perl_magic_setsig(), don't discard and then recreate the signal name SV.

diff --git a/mg.c b/mg.c
index 819e105..1bc5bf7 100644 (file)
--- a/mg.c
+++ b/mg.c
@@ -1439,14 +1439,23 @@ Perl_magic_setsig(pTHX_ SV *sv, MAGIC *mg)
 #ifdef FAKE_DEFAULT_SIGNAL_HANDLERS
        PL_sig_defaulting[i] = 0;
 #endif
-       SvREFCNT_dec(PL_psig_name[i]);
        to_dec = PL_psig_ptr[i];
        if (sv) {
            PL_psig_ptr[i] = SvREFCNT_inc_simple_NN(sv);
            SvTEMP_off(sv); /* Make sure it doesn't go away on us */
-           PL_psig_name[i] = newSVpvn(s, len);
-           SvREADONLY_on(PL_psig_name[i]);
+
+           /* Signals don't change name during the program's execution, so once
+              they're cached in the appropriate slot of PL_psig_name, they can
+              stay there.
+
+              Ideally we'd find some way of making SVs at (C) compile time, or
+              at least, doing most of the work.  */
+           if (!PL_psig_name[i]) {
+               PL_psig_name[i] = newSVpvn(s, len);
+               SvREADONLY_on(PL_psig_name[i]);
+           }
        } else {
+           SvREFCNT_dec(PL_psig_name[i]);
            PL_psig_name[i] = NULL;
            PL_psig_ptr[i] = NULL;
        }