diff --git a/changes/bug18977 b/changes/bug18977
new file mode 100644
index 0000000000..3f46b09fba
--- /dev/null
+++ b/changes/bug18977
@@ -0,0 +1,4 @@
+  o Minor bugfixes (time handling):
+    - When correcting a corrupt 'struct tm' value, fill in the tm_wday
+      field. Otherwise, our unit tests crash on Windows.
+      Fixes bug 18977; bugfix on 0.2.2.25-alpha.
diff --git a/src/common/compat.c b/src/common/compat.c
index af61f024ef..23eaa134cf 100644
--- a/src/common/compat.c
+++ b/src/common/compat.c
@@ -2923,6 +2923,7 @@ correct_tm(int islocal, const time_t *timep, struct tm *resultbuf,
       r->tm_mon = 11;
       r->tm_mday = 31;
       r->tm_yday = 364;
+      r->tm_wday = 6;
       r->tm_hour = 23;
       r->tm_min = 59;
       r->tm_sec = 59;
@@ -2931,6 +2932,7 @@ correct_tm(int islocal, const time_t *timep, struct tm *resultbuf,
       r->tm_mon = 0;
       r->tm_mday = 1;
       r->tm_yday = 0;
+      r->tm_wday = 0;
       r->tm_hour = 0;
       r->tm_min = 0;
       r->tm_sec = 0;
@@ -2948,6 +2950,7 @@ correct_tm(int islocal, const time_t *timep, struct tm *resultbuf,
       r->tm_mon = 0;
       r->tm_mday = 1;
       r->tm_yday = 0;
+      r->tm_wday = 0;
       r->tm_hour = 0;
       r->tm_min = 0 ;
       r->tm_sec = 0;
@@ -2961,6 +2964,7 @@ correct_tm(int islocal, const time_t *timep, struct tm *resultbuf,
       r->tm_mon = 11;
       r->tm_mday = 31;
       r->tm_yday = 364;
+      r->tm_wday = 6;
       r->tm_hour = 23;
       r->tm_min = 59;
       r->tm_sec = 59;
diff --git a/src/common/util.c b/src/common/util.c
index 008c682b3b..f3effe0957 100644
--- a/src/common/util.c
+++ b/src/common/util.c
@@ -1723,6 +1723,7 @@ parse_iso_time_(const char *cp, time_t *t, int strict)
   st_tm.tm_hour = hour;
   st_tm.tm_min = minute;
   st_tm.tm_sec = second;
+  st_tm.tm_wday = 0; /* Should be ignored. */
 
   if (st_tm.tm_year < 70) {
     char *esc = esc_for_log(cp);
@@ -1790,6 +1791,7 @@ parse_http_time(const char *date, struct tm *tm)
   tm->tm_hour = (int)tm_hour;
   tm->tm_min = (int)tm_min;
   tm->tm_sec = (int)tm_sec;
+  tm->tm_wday = 0; /* Leave this unset. */
 
   month[3] = '\0';
   /* Okay, now decode the month. */