Merge branch 'remove-is_utc' of https://github.com/ksuther/libical into ksuther-remove-is_utc

17 files changed, 29 insertions, 102 deletions

diff --git a/doc/UsingLibical.txt b/doc/UsingLibical.txt
index 688898da..9eecded4 100644
--- a/doc/UsingLibical.txt
+++ b/doc/UsingLibical.txt
@@ -839,13 +839,10 @@ struct icaltimetype {
 
   int second;
 
-  int is_utc; /* 1-> time is in UTC timezone */
-
   int is_date; /* 1 -> interpret this as date. */ };
 
 The year, month, day, hour, minute and second fields hold the broken-out
-time values. The is_utc field distinguishes between times in UTC and
-a local time zone. The is_date field indicates if the time should
+time values. The is_date field indicates if the time should
 be interpreted only as a date. If it is a date, the hour, minute and
 second fields are assumed to be zero, regardless of their actual vaules.
 
@@ -1365,8 +1362,6 @@ struct icaltimetype
 
         int second;
 
-         int is_utc;
-
         int is_date;
 
         const char* zone;
diff --git a/src/java/ICalTimeType.java b/src/java/ICalTimeType.java
index cf4ee407..15cf8715 100644
--- a/src/java/ICalTimeType.java
+++ b/src/java/ICalTimeType.java
@@ -79,15 +79,6 @@ public class ICalTimeType
 	return second;
     }
 
-    public void setIs_utc(boolean lcl_arg0)
-    {
-	is_utc = lcl_arg0 ? 1 : 0;
-    }
-    public boolean getIs_utc()
-    {
-	return is_utc == 0 ? false : true;
-    }
-
     public void setIs_date(boolean lcl_arg0)
     {
 	is_date = lcl_arg0 ? 1 : 0;
@@ -138,7 +129,6 @@ public class ICalTimeType
     private int	hour;
     private int	minute;
     private int	second;
-    private int	is_utc;
     private int	is_date;
     private String	zone = new String();	//   Converted from char*
 }
diff --git a/src/java/jniICalPeriodType_cxx.cpp b/src/java/jniICalPeriodType_cxx.cpp
index 4cfbfe82..3f4ea10a 100644
--- a/src/java/jniICalPeriodType_cxx.cpp
+++ b/src/java/jniICalPeriodType_cxx.cpp
@@ -44,7 +44,6 @@ void  jni_SetStart_in_ICalPeriodType(struct ICalPeriodType* __ICalPeriodType_, J
     jni_SetHour_in_ICalTimeType(&(__ICalPeriodType_->start), env, lcl_jobj0);
     jni_SetMinute_in_ICalTimeType(&(__ICalPeriodType_->start), env, lcl_jobj0);
     jni_SetSecond_in_ICalTimeType(&(__ICalPeriodType_->start), env, lcl_jobj0);
-    jni_SetIs_utc_in_ICalTimeType(&(__ICalPeriodType_->start), env, lcl_jobj0);
     jni_SetIs_date_in_ICalTimeType(&(__ICalPeriodType_->start), env, lcl_jobj0);
     jni_SetZone_in_ICalTimeType(&(__ICalPeriodType_->start), env, lcl_jobj0);
 }
@@ -59,7 +58,6 @@ void jni_GetStart_from_ICalPeriodType(struct ICalPeriodType* __ICalPeriodType_,
     jni_GetHour_from_ICalTimeType(&(__ICalPeriodType_->start), env, lcl_jobj0);
     jni_GetMinute_from_ICalTimeType(&(__ICalPeriodType_->start), env, lcl_jobj0);
     jni_GetSecond_from_ICalTimeType(&(__ICalPeriodType_->start), env, lcl_jobj0);
-    jni_GetIs_utc_from_ICalTimeType(&(__ICalPeriodType_->start), env, lcl_jobj0);
     jni_GetIs_date_from_ICalTimeType(&(__ICalPeriodType_->start), env, lcl_jobj0);
     jni_GetZone_from_ICalTimeType(&(__ICalPeriodType_->start), env, lcl_jobj0);
 }
@@ -74,7 +72,6 @@ void  jni_SetEnd_in_ICalPeriodType(struct ICalPeriodType* __ICalPeriodType_, JNI
     jni_SetHour_in_ICalTimeType(&(__ICalPeriodType_->end), env, lcl_jobj0);
     jni_SetMinute_in_ICalTimeType(&(__ICalPeriodType_->end), env, lcl_jobj0);
     jni_SetSecond_in_ICalTimeType(&(__ICalPeriodType_->end), env, lcl_jobj0);
-    jni_SetIs_utc_in_ICalTimeType(&(__ICalPeriodType_->end), env, lcl_jobj0);
     jni_SetIs_date_in_ICalTimeType(&(__ICalPeriodType_->end), env, lcl_jobj0);
     jni_SetZone_in_ICalTimeType(&(__ICalPeriodType_->end), env, lcl_jobj0);
 }
@@ -89,7 +86,6 @@ void jni_GetEnd_from_ICalPeriodType(struct ICalPeriodType* __ICalPeriodType_, JN
     jni_GetHour_from_ICalTimeType(&(__ICalPeriodType_->end), env, lcl_jobj0);
     jni_GetMinute_from_ICalTimeType(&(__ICalPeriodType_->end), env, lcl_jobj0);
     jni_GetSecond_from_ICalTimeType(&(__ICalPeriodType_->end), env, lcl_jobj0);
-    jni_GetIs_utc_from_ICalTimeType(&(__ICalPeriodType_->end), env, lcl_jobj0);
     jni_GetIs_date_from_ICalTimeType(&(__ICalPeriodType_->end), env, lcl_jobj0);
     jni_GetZone_from_ICalTimeType(&(__ICalPeriodType_->end), env, lcl_jobj0);
 }
diff --git a/src/java/jniICalRecurrenceType_cxx.cpp b/src/java/jniICalRecurrenceType_cxx.cpp
index af4c112c..9b463301 100644
--- a/src/java/jniICalRecurrenceType_cxx.cpp
+++ b/src/java/jniICalRecurrenceType_cxx.cpp
@@ -64,7 +64,6 @@ void  jni_SetUntil_in_ICalRecurrenceType(struct ICalRecurrenceType* __ICalRecurr
     jni_SetHour_in_ICalTimeType(&(__ICalRecurrenceType_->until), env, lcl_jobj0);
     jni_SetMinute_in_ICalTimeType(&(__ICalRecurrenceType_->until), env, lcl_jobj0);
     jni_SetSecond_in_ICalTimeType(&(__ICalRecurrenceType_->until), env, lcl_jobj0);
-    jni_SetIs_utc_in_ICalTimeType(&(__ICalRecurrenceType_->until), env, lcl_jobj0);
     jni_SetIs_date_in_ICalTimeType(&(__ICalRecurrenceType_->until), env, lcl_jobj0);
     jni_SetZone_in_ICalTimeType(&(__ICalRecurrenceType_->until), env, lcl_jobj0);
 }
@@ -79,7 +78,6 @@ void jni_GetUntil_from_ICalRecurrenceType(struct ICalRecurrenceType* __ICalRecur
     jni_GetHour_from_ICalTimeType(&(__ICalRecurrenceType_->until), env, lcl_jobj0);
     jni_GetMinute_from_ICalTimeType(&(__ICalRecurrenceType_->until), env, lcl_jobj0);
     jni_GetSecond_from_ICalTimeType(&(__ICalRecurrenceType_->until), env, lcl_jobj0);
-    jni_GetIs_utc_from_ICalTimeType(&(__ICalRecurrenceType_->until), env, lcl_jobj0);
     jni_GetIs_date_from_ICalTimeType(&(__ICalRecurrenceType_->until), env, lcl_jobj0);
     jni_GetZone_from_ICalTimeType(&(__ICalRecurrenceType_->until), env, lcl_jobj0);
 }
diff --git a/src/java/jniICalTimeType_cxx.cpp b/src/java/jniICalTimeType_cxx.cpp
index b4012aa9..8ee2d694 100644
--- a/src/java/jniICalTimeType_cxx.cpp
+++ b/src/java/jniICalTimeType_cxx.cpp
@@ -27,7 +27,6 @@ static jfieldID ICalTimeType_Day_FID;
 static jfieldID ICalTimeType_Hour_FID;
 static jfieldID ICalTimeType_Minute_FID;
 static jfieldID ICalTimeType_Second_FID;
-static jfieldID ICalTimeType_Is_utc_FID;
 static jfieldID ICalTimeType_Is_date_FID;
 static jfieldID ICalTimeType_Zone_FID;
 
@@ -40,7 +39,6 @@ void initICalTimeTypeFieldIDs(JNIEnv* env, jclass clazz)
     ICalTimeType_Hour_FID = env->GetFieldID(clazz, "hour", "I");
     ICalTimeType_Minute_FID = env->GetFieldID(clazz, "minute", "I");
     ICalTimeType_Second_FID = env->GetFieldID(clazz, "second", "I");
-    ICalTimeType_Is_utc_FID = env->GetFieldID(clazz, "is_utc", "I");
     ICalTimeType_Is_date_FID = env->GetFieldID(clazz, "is_date", "I");
     ICalTimeType_Zone_FID = env->GetFieldID(clazz, "zone", "Ljava/lang/String;");
 }
@@ -105,16 +103,6 @@ void jni_GetSecond_from_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEn
     __ICalTimeType_->second = env->GetIntField(thisICalTimeType, ICalTimeType_Second_FID);
 }
 
-void  jni_SetIs_utc_in_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv *env, jobject thisICalTimeType)
-{
-    env->SetIntField(thisICalTimeType, ICalTimeType_Is_utc_FID, (jint) __ICalTimeType_->is_utc);
-}
-
-void jni_GetIs_utc_from_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv *env, jobject thisICalTimeType)
-{
-    __ICalTimeType_->is_utc = env->GetIntField(thisICalTimeType, ICalTimeType_Is_utc_FID);
-}
-
 void  jni_SetIs_date_in_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv *env, jobject thisICalTimeType)
 {
     env->SetIntField(thisICalTimeType, ICalTimeType_Is_date_FID, (jint) __ICalTimeType_->is_date);
@@ -144,7 +132,6 @@ void jni_SetAll_in_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv* en
     jni_SetHour_in_ICalTimeType(__ICalTimeType_, env, thisICalTimeType);
     jni_SetMinute_in_ICalTimeType(__ICalTimeType_, env, thisICalTimeType);
     jni_SetSecond_in_ICalTimeType(__ICalTimeType_, env, thisICalTimeType);
-    jni_SetIs_utc_in_ICalTimeType(__ICalTimeType_, env, thisICalTimeType);
     jni_SetIs_date_in_ICalTimeType(__ICalTimeType_, env, thisICalTimeType);
     jni_SetZone_in_ICalTimeType(__ICalTimeType_, env, thisICalTimeType);
 }
@@ -158,7 +145,6 @@ void jni_GetAll_from_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv*
     jni_GetHour_from_ICalTimeType(__ICalTimeType_, env, thisICalTimeType);
     jni_GetMinute_from_ICalTimeType(__ICalTimeType_, env, thisICalTimeType);
     jni_GetSecond_from_ICalTimeType(__ICalTimeType_, env, thisICalTimeType);
-    jni_GetIs_utc_from_ICalTimeType(__ICalTimeType_, env, thisICalTimeType);
     jni_GetIs_date_from_ICalTimeType(__ICalTimeType_, env, thisICalTimeType);
     jni_GetZone_from_ICalTimeType(__ICalTimeType_, env, thisICalTimeType);
 }
diff --git a/src/java/jniICalTimeType_cxx.h b/src/java/jniICalTimeType_cxx.h
index f74b6f80..06428398 100644
--- a/src/java/jniICalTimeType_cxx.h
+++ b/src/java/jniICalTimeType_cxx.h
@@ -42,8 +42,6 @@ void  jni_SetMinute_in_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv
 void jni_GetMinute_from_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv *env, jobject thisICalTimeType);
 void  jni_SetSecond_in_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv *env, jobject thisICalTimeType);
 void jni_GetSecond_from_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv *env, jobject thisICalTimeType);
-void  jni_SetIs_utc_in_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv *env, jobject thisICalTimeType);
-void jni_GetIs_utc_from_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv *env, jobject thisICalTimeType);
 void  jni_SetIs_date_in_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv *env, jobject thisICalTimeType);
 void jni_GetIs_date_from_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv *env, jobject thisICalTimeType);
 void  jni_SetZone_in_ICalTimeType(struct ICalTimeType* __ICalTimeType_, JNIEnv *env, jobject thisICalTimeType);
diff --git a/src/java/jniICalTriggerType_cxx.cpp b/src/java/jniICalTriggerType_cxx.cpp
index c8718e11..7b9d860c 100644
--- a/src/java/jniICalTriggerType_cxx.cpp
+++ b/src/java/jniICalTriggerType_cxx.cpp
@@ -41,7 +41,6 @@ void  jni_SetTime_in_ICalTriggerType(struct ICalTriggerType* __ICalTriggerType_,
     jni_SetHour_in_ICalTimeType(&(__ICalTriggerType_->time), env, lcl_jobj0);
     jni_SetMinute_in_ICalTimeType(&(__ICalTriggerType_->time), env, lcl_jobj0);
     jni_SetSecond_in_ICalTimeType(&(__ICalTriggerType_->time), env, lcl_jobj0);
-    jni_SetIs_utc_in_ICalTimeType(&(__ICalTriggerType_->time), env, lcl_jobj0);
     jni_SetIs_date_in_ICalTimeType(&(__ICalTriggerType_->time), env, lcl_jobj0);
     jni_SetZone_in_ICalTimeType(&(__ICalTriggerType_->time), env, lcl_jobj0);
 }
@@ -56,7 +55,6 @@ void jni_GetTime_from_ICalTriggerType(struct ICalTriggerType* __ICalTriggerType_
     jni_GetHour_from_ICalTimeType(&(__ICalTriggerType_->time), env, lcl_jobj0);
     jni_GetMinute_from_ICalTimeType(&(__ICalTriggerType_->time), env, lcl_jobj0);
     jni_GetSecond_from_ICalTimeType(&(__ICalTriggerType_->time), env, lcl_jobj0);
-    jni_GetIs_utc_from_ICalTimeType(&(__ICalTriggerType_->time), env, lcl_jobj0);
     jni_GetIs_date_from_ICalTimeType(&(__ICalTriggerType_->time), env, lcl_jobj0);
     jni_GetZone_from_ICalTimeType(&(__ICalTriggerType_->time), env, lcl_jobj0);
 }
diff --git a/src/java/testjni.java b/src/java/testjni.java
index a7eb5886..d90c327b 100644
--- a/src/java/testjni.java
+++ b/src/java/testjni.java
@@ -37,7 +37,7 @@ public class testjni
 		starttime.setHour(18);
 		starttime.setMinute(0);
 		starttime.setSecond(0);
-		starttime.setIs_utc(true);
+		starttime.setZone("UTC");
 		System.out.println("done creating starttime");
 
 		ICalTimeType endtime = new ICalTimeType();
@@ -47,7 +47,7 @@ public class testjni
 		endtime.setHour(8);
 		endtime.setMinute(0);
 		endtime.setSecond(0);
-		endtime.setIs_utc(true);
+		endtime.setZone("UTC");
 		System.out.println("done creating endtime");
 
 
@@ -258,7 +258,7 @@ public class testjni
 		time_tma.setHour(2);
 		time_tma.setMinute(2);
 		time_tma.setSecond(2);
-		time_tma.setIs_utc(true);
+		time_tma.setZone("UTC");
 
 		ic.set_recurrenceid(time_tma);
 
@@ -299,7 +299,7 @@ public class testjni
                 duetime.setHour(18);
                 duetime.setMinute(0);
                 duetime.setSecond(0);
-                duetime.setIs_utc(true);
+                duetime.setZone("UTC");
                 System.out.println("done creating duetime");
 
                 statusProp.set_status(ICalProperty.ICalPropertyStatus.ICAL_STATUS_COMPLETED);
diff --git a/src/libical-glib/api/i-cal-timetype.xml b/src/libical-glib/api/i-cal-timetype.xml
index 01e80853..685a9400 100644
--- a/src/libical-glib/api/i-cal-timetype.xml
+++ b/src/libical-glib/api/i-cal-timetype.xml
@@ -24,10 +24,9 @@
 	timetype.hour = 0;
 	timetype.minute = 0;
 	timetype.second = 0;
-	timetype.is_utc = 1;
 	timetype.is_date = 0;
 	timetype.is_daylight = 0;
-	timetype.zone = NULL;
+	timetype.zone = icaltimezone_get_utc_timezone();
 	return timetype;</custom>
     </method>
     <method name="i_cal_timetype_new" corresponds="CUSTOM" kind="constructor" since="1.0">
@@ -121,17 +120,10 @@
     </method>
     <method name="i_cal_timetype_is_utc" corresponds="CUSTOM" kind="get" since="1.0">
         <parameter type="ICalTimetype *" name="timetype" comment="The #ICalTimetype to be queried."/>
-        <returns type="gint" comment="The is_utc." />
-        <comment xml:space="preserve">Get the is_utc of #ICalTimetype.</comment>
+        <returns type="gint" comment="If the time is in UTC." />
+        <comment xml:space="preserve">Get if the #ICalTimetype is in UTC.</comment>
         <custom>	g_return_val_if_fail (timetype != NULL, 0);
-	return ((struct icaltimetype *)i_cal_object_get_native ((ICalObject *)timetype))->is_utc;</custom>
-    </method>
-    <method name="i_cal_timetype_set_is_utc" corresponds="CUSTOM" kind="set" since="1.0">
-        <parameter type="ICalTimetype *" name="timetype" comment="The #ICalTimetype to be set."/>
-        <parameter type="gint" name="is_utc" comment="The is_utc."/>
-        <comment>Set the is_utc of #ICalTimetype.</comment>
-        <custom>	g_return_if_fail (timetype != NULL &amp;&amp; I_CAL_IS_TIMETYPE (timetype));
-	((struct icaltimetype *)i_cal_object_get_native ((ICalObject *)timetype))->is_utc = is_utc;</custom>
+	return icaltime_is_utc(*(struct icaltimetype *)i_cal_object_get_native ((ICalObject *)timetype));</custom>
     </method>
     <method name="i_cal_timetype_is_date" corresponds="CUSTOM" kind="get" since="1.0">
         <parameter type="ICalTimetype *" name="timetype" comment="The #ICalTimetype to be queried."/>
diff --git a/src/libical/icaltime.c b/src/libical/icaltime.c
index 32b73160..cace5eb9 100644
--- a/src/libical/icaltime.c
+++ b/src/libical/icaltime.c
@@ -225,9 +225,8 @@ struct icaltimetype icaltime_from_timet_with_zone(const time_t tm, const int is_
     tt.minute = t.tm_min;
     tt.second = t.tm_sec;
     tt.is_date = 0;
-    tt.is_utc = (zone == utc_zone) ? 1 : 0;
     tt.is_daylight = 0;
-    tt.zone = NULL;
+    tt.zone = (zone == NULL) ? NULL : utc_zone;
 
     /* Use our timezone functions to convert to the required timezone. */
     icaltimezone_convert_time(&tt, utc_zone, (icaltimezone *) zone);
@@ -366,7 +365,7 @@ char *icaltime_as_ical_string_r(const struct icaltimetype tt)
     } else {
         const char *fmt;
 
-        if (tt.is_utc) {
+        if (icaltime_is_utc(tt)) {
             fmt = "%04d%02d%02dT%02d%02d%02dZ";
         } else {
             fmt = "%04d%02d%02dT%02d%02d%02d";
@@ -413,17 +412,14 @@ struct icaltimetype icaltime_from_string(const char *str)
     size = strlen(str);
 
     if ((size == 15) || (size == 19)) { /* floating time with/without separators */
-        tt.is_utc = 0;
         tt.is_date = 0;
     } else if ((size == 16) || (size == 20)) {  /* UTC time, ends in 'Z' */
         if ((str[size-1] != 'Z'))
             goto FAIL;
 
-        tt.is_utc = 1;
         tt.zone = icaltimezone_get_utc_timezone();
         tt.is_date = 0;
     } else if ((size == 8) || (size == 10)) {   /* A DATE */
-        tt.is_utc = 0;
         tt.is_date = 1;
     } else {    /* error */
         goto FAIL;
@@ -689,8 +685,7 @@ struct icaltimetype icaltime_null_date(void)
  */
 int icaltime_is_valid_time(const struct icaltimetype t)
 {
-    if (t.is_utc > 1 || t.is_utc < 0 ||
-        t.year < 0 || t.year > 3000 || t.is_date > 1 || t.is_date < 0) {
+    if (t.year < 0 || t.year > 3000 || t.is_date > 1 || t.is_date < 0) {
         return 0;
     } else {
         return 1;
@@ -710,7 +705,7 @@ int icaltime_is_date(const struct icaltimetype t)
  */
 int icaltime_is_utc(const struct icaltimetype t)
 {
-    return t.is_utc;
+    return t.zone == icaltimezone_get_utc_timezone();
 }
 
 /**
@@ -737,10 +732,7 @@ int icaltime_compare(const struct icaltimetype a_in, const struct icaltimetype b
 
     /* We only need to perform time zone conversion if times aren't in the same time zone
        or neither of them is floating (zone equals NULL) */
-    if ((a_in.zone != b_in.zone || a_in.is_utc != b_in.is_utc) &&
-        ((a_in.zone != NULL && b_in.zone != NULL) ||
-         (a_in.zone != NULL && b_in.is_utc) ||
-         (a_in.is_utc && b_in.zone != NULL))) {
+    if (a_in.zone != b_in.zone && a_in.zone != NULL && b_in.zone != NULL) {
         a = icaltime_convert_to_zone(a_in, icaltimezone_get_utc_timezone());
         b = icaltime_convert_to_zone(b_in, icaltimezone_get_utc_timezone());
     } else {
@@ -979,7 +971,7 @@ struct icaltimetype icaltime_convert_to_zone(const struct icaltimetype tt, icalt
     }
 
     /* If it's a floating time we don't want to adjust the time */
-    if (tt.zone != NULL || tt.is_utc) {
+    if (tt.zone != NULL) {
         icaltimezone *from_zone = (icaltimezone *) tt.zone;
 
         if (!from_zone) {
@@ -990,11 +982,6 @@ struct icaltimetype icaltime_convert_to_zone(const struct icaltimetype tt, icalt
     }
 
     ret.zone = zone;
-    if (zone == icaltimezone_get_utc_timezone()) {
-        ret.is_utc = 1;
-    } else {
-        ret.is_utc = 0;
-    }
 
     return ret;
 }
@@ -1031,11 +1018,6 @@ struct icaltimetype icaltime_set_timezone(struct icaltimetype *t, const icaltime
     }
 
     t->zone = zone;
-    if (zone == icaltimezone_get_utc_timezone()) {
-        t->is_utc = 1;
-    } else {
-        t->is_utc = 0;
-    }
 
     return *t;
 }
diff --git a/src/libical/icaltime.h b/src/libical/icaltime.h
index 6f35b53f..2d7e2f8a 100644
--- a/src/libical/icaltime.h
+++ b/src/libical/icaltime.h
@@ -111,8 +111,6 @@ struct icaltimetype
     int minute;
     int second;
 
-    int is_utc;         /**< 1-> time is in UTC timezone */
-
     int is_date;        /**< 1 -> interpret this as date. */
 
     int is_daylight;    /**< 1 -> time is in daylight savings time. */
diff --git a/src/libical/icaltimezone.c b/src/libical/icaltimezone.c
index 5fa7531b..f5066822 100644
--- a/src/libical/icaltimezone.c
+++ b/src/libical/icaltimezone.c
@@ -624,7 +624,7 @@ void icaltimezone_expand_vtimezone(icalcomponent *comp, int end_year, icalarray
             /* If the rrule UNTIL value is set and is in UTC, we convert it to
                a local time, since the recurrence code has no way to convert
                it itself. */
-            if (!icaltime_is_null_time(rrule.until) && rrule.until.is_utc) {
+            if (!icaltime_is_null_time(rrule.until) && icaltime_is_utc(rrule.until)) {
 #if 0
                 printf("  Found RRULE UNTIL in UTC.\n");
 #endif
@@ -633,7 +633,7 @@ void icaltimezone_expand_vtimezone(icalcomponent *comp, int end_year, icalarray
                    since that is the offset from UTC that will be in effect
                    when each of the RRULE occurrences happens. */
                 icaltime_adjust(&rrule.until, 0, 0, 0, change.prev_utc_offset);
-                rrule.until.is_utc = 0;
+                rrule.until.zone = NULL;
             }
 
             /* Add the dtstart to changes, otherwise some oddly-defined VTIMEZONE
@@ -1350,7 +1350,6 @@ static struct icaltimetype tm_to_icaltimetype(struct tm *tm)
     itt.month = tm->tm_mon + 1;
     itt.year = tm->tm_year + 1900;
 
-    itt.is_utc = 0;
     itt.is_date = 0;
 
     return itt;
diff --git a/src/libical/icaltz-util.c b/src/libical/icaltz-util.c
index 1dfdf5eb..b86bdca3 100644
--- a/src/libical/icaltz-util.c
+++ b/src/libical/icaltz-util.c
@@ -456,7 +456,7 @@ icalcomponent *icaltzutil_fetch_timezone(const char *location)
                         types[prev_idx].gmtoff != prev_daylight_gmtoff) {
                     // Set UNTIL of the previous component's recurrence
                     icaltime_adjust(&prev_daylight_time, 0, 0, 0, -types[prev_idx].gmtoff);
-                    prev_daylight_time.is_utc = 1;
+                    prev_daylight_time.zone = icaltimezone_get_utc_timezone();
 
                     daylight_recur.until = prev_daylight_time;
                     icalproperty_set_rrule(cur_daylight_rrule_property, daylight_recur);
@@ -489,7 +489,7 @@ icalcomponent *icaltzutil_fetch_timezone(const char *location)
                         standard_recur.by_day[0] != by_day ||
                         types[prev_idx].gmtoff != prev_standard_gmtoff) {
                     icaltime_adjust(&prev_standard_time, 0, 0, 0, -types[prev_idx].gmtoff);
-                    prev_standard_time.is_utc = 1;
+                    prev_standard_time.zone = icaltimezone_get_utc_timezone();
 
                     standard_recur.until = prev_standard_time;
                     icalproperty_set_rrule(cur_standard_rrule_property, standard_recur);
@@ -503,7 +503,7 @@ icalcomponent *icaltzutil_fetch_timezone(const char *location)
                     if (cur_daylight_comp && daylight_recur.by_month[0] == icaltime.month &&
                             daylight_recur.by_day[0] == by_day) {
                         icaltime_adjust(&prev_daylight_time, 0, 0, 0, -types[prev_idx].gmtoff);
-                        prev_daylight_time.is_utc = 1;
+                        prev_daylight_time.zone = icaltimezone_get_utc_timezone();
 
                         daylight_recur.until = prev_daylight_time;
                         icalproperty_set_rrule(cur_daylight_rrule_property, daylight_recur);
@@ -562,7 +562,7 @@ icalcomponent *icaltzutil_fetch_timezone(const char *location)
     // and then insert a new component to indicate the time zone doesn't transition anymore
     if (cur_daylight_comp && icaltime_as_timet(prev_daylight_time) < now) {
         icaltime_adjust(&prev_prev_daylight_time, 0, 0, 0, -prev_daylight_gmtoff);
-        prev_prev_daylight_time.is_utc = 1;
+        prev_prev_daylight_time.zone = icaltimezone_get_utc_timezone();
 
         daylight_recur.until = prev_prev_daylight_time;
         icalproperty_set_rrule(cur_daylight_rrule_property, daylight_recur);
@@ -581,7 +581,7 @@ icalcomponent *icaltzutil_fetch_timezone(const char *location)
 
     if (cur_standard_comp && icaltime_as_timet(prev_standard_time) < now) {
         icaltime_adjust(&prev_prev_standard_time, 0, 0, 0, -prev_standard_gmtoff);
-        prev_prev_standard_time.is_utc = 1;
+        prev_prev_standard_time.zone = icaltimezone_get_utc_timezone();
 
         standard_recur.until = prev_prev_standard_time;
         icalproperty_set_rrule(cur_standard_rrule_property, standard_recur);
diff --git a/src/libicalss/icalclassify.c b/src/libicalss/icalclassify.c
index e7f8f52d..30536140 100644
--- a/src/libicalss/icalclassify.c
+++ b/src/libicalss/icalclassify.c
@@ -663,7 +663,7 @@ icalproperty_xlicclass icalclassify(icalcomponent *c, icalcomponent *match, cons
 
     /* Determine if the incoming component is obsoleted by the match */
     if (match != 0 && (comp_parts.method == ICAL_METHOD_REQUEST)) {
-        assert(!((comp_parts.dtstamp.is_utc == 1) ^ (match_parts.dtstamp.is_utc == 1)));
+        assert(!((icaltime_is_utc(comp_parts.dtstamp) == 1) ^ (icaltime_is_utc(match_parts.dtstamp) == 1)));
 
         if (comp_parts.sequence < match_parts.sequence &&
             icaltime_compare(comp_parts.dtstamp, match_parts.dtstamp) > 0) {
diff --git a/src/libicalvcal/icalvcal.c b/src/libicalvcal/icalvcal.c
index fe1cf591..9acb8824 100644
--- a/src/libicalvcal/icalvcal.c
+++ b/src/libicalvcal/icalvcal.c
@@ -40,6 +40,7 @@
 #include "icalvcal.h"
 #include "icalerror.h"
 #include "icalvalue.h"
+#include "icaltimezone.h"
 #include "icalversion.h"        /* for ICAL_PACKAGE */
 
 #include <stddef.h>     /* for ptrdiff_t */
@@ -147,8 +148,8 @@ static void convert_floating_time_to_utc(struct icaltimetype *itt)
     itt->minute = utc_tm.tm_min;
     itt->second = utc_tm.tm_sec;
 
-    /* Set the is_utc flag. */
-    itt->is_utc = 1;
+    /* Set the zone to UTC. */
+    itt->zone = icaltimezone_get_utc_timezone();
 }
 
 static void icalvcal_traverse_objects(VObject *,
@@ -302,7 +303,7 @@ static int get_alarm_properties(icalcomponent *comp, VObject *object,
                 t.duration = icaldurationtype_null_duration();
 
                 /* If it is a floating time, convert it to a UTC time. */
-                if (!t.time.is_utc)
+                if (t.time.zone == NULL)
                     convert_floating_time_to_utc(&t.time);
 
                 /* Create a TRIGGER property. */
@@ -747,7 +748,7 @@ static void *utc_datetime_prop(int icaltype, VObject *object, icalcomponent *com
     itt = icaltime_from_string(s);
 
     /* If it is a floating time, convert it to a UTC time. */
-    if (!itt.is_utc)
+    if (itt.zone == NULL)
         convert_floating_time_to_utc(&itt);
 
     value = icalvalue_new_datetime(itt);
@@ -845,7 +846,7 @@ static const char *rrule_parse_duration(const char *s, struct icalrecurrencetype
            don't really know what timezone the vCalendar times are in. So if
            it can be converted to a DATE value, we do that. Otherwise we just
            use the current Unix timezone. Should be OK 99% of the time. */
-        if (!recur->until.is_utc) {
+        if (!icaltime_is_utc(recur->until)) {
             if (recur->until.hour == 0 &&
                 recur->until.minute == 0 &&
                 recur->until.second == 0) {
diff --git a/src/python/LibicalWrap_icaltime.i b/src/python/LibicalWrap_icaltime.i
index c1508089..43fc9127 100644
--- a/src/python/LibicalWrap_icaltime.i
+++ b/src/python/LibicalWrap_icaltime.i
@@ -164,7 +164,6 @@ def icaltimetype_from_datetime(dt):
     if dt.tzinfo:
         # TODO: convert to the right timezone, assume for now we are UTC
         tt.zone = 0
-        tt.is_utc = True
     tt.is_date = False
     tt.isdaylight = False
     
diff --git a/src/test/regression.c b/src/test/regression.c
index b68f5d35..63b95434 100644
--- a/src/test/regression.c
+++ b/src/test/regression.c
@@ -408,11 +408,6 @@ void test_icaltime_compare_utc_zone()
     b = icaltime_from_string("20170130T103000");
     b.zone = icaltimezone_get_builtin_timezone("America/Los_Angeles");
     int_is("a < b", icaltime_compare(a, b), -1);
-
-    /* test comparing times across time zones (where UTC is specified by is_utc and zone is NULL) */
-    a.zone = NULL;
-    int_is("a.is_utc", a.is_utc, 1);
-    int_is("a < b", icaltime_compare(a, b), -1);
 }
 
 void test_parameters()