add -DM flag to track smartmatch resolution

1 files changed, 2 insertions, 1 deletions

diff --git a/perl.c b/perl.c
index 9ef9cd7116..6c1b5434bb 100644
--- a/perl.c
+++ b/perl.c
@@ -2863,6 +2863,7 @@ Perl_get_debug_opts(pTHX_ const char **s, bool givehelp)
       "  C  Copy On Write",
       "  A  Consistency checks on internal structures",
       "  q  quiet - currently only suppresses the 'EXECUTING' message",
+      "  M  trace smart match resolution",
       NULL
     };
     int i = 0;
@@ -2871,7 +2872,7 @@ Perl_get_debug_opts(pTHX_ const char **s, bool givehelp)
 
     if (isALPHA(**s)) {
 	/* if adding extra options, remember to update DEBUG_MASK */
-	static const char debopts[] = "psltocPmfrxuUHXDSTRJvCAq";
+	static const char debopts[] = "psltocPmfrxuUHXDSTRJvCAqM";
 
 	for (; isALNUM(**s); (*s)++) {
 	    const char * const d = strchr(debopts,**s);