diff --git a/qtools/qcstring.cpp b/qtools/qcstring.cpp
index 45ccef9..35b9bb8 100644
--- a/qtools/qcstring.cpp
+++ b/qtools/qcstring.cpp
@@ -460,6 +460,12 @@ ulong QCString::toULong(bool *ok) const
   return s.toULong(ok);
 }
 
+uint64 QCString::toUInt64(bool *ok) const
+{
+  QString s(data());
+  return s.toUInt64(ok);
+}
+
 QCString &QCString::setNum(short n)
 {
   return setNum((long)n);
diff --git a/qtools/qcstring.h b/qtools/qcstring.h
index d8ce074..4f15b18 100644
--- a/qtools/qcstring.h
+++ b/qtools/qcstring.h
@@ -288,6 +288,7 @@ public:
     uint toUInt( bool *ok=0 ) const;
     long toLong( bool *ok=0 ) const;
     ulong toULong( bool *ok=0 )	const;
+    uint64 toUInt64( bool *ok=0 ) const;
     QCString &setNum(short n);
     QCString &setNum(ushort n);
     QCString &setNum(int n);
diff --git a/qtools/qstring.cpp b/qtools/qstring.cpp
index f51c0d4..458fd53 100644
--- a/qtools/qstring.cpp
+++ b/qtools/qstring.cpp
@@ -13935,6 +13935,60 @@ bye:
 }
 
 /*!
+  Returns the string converted to an <code>unsigned long</code>
+  value.
+
+  If \a ok is non-null, \a *ok is set to TRUE if there are no
+  conceivable errors, and FALSE if the string is not a number at all,
+  or if it has trailing garbage.
+*/
+
+uint64 QString::toUInt64( bool *ok, int base ) const
+{
+    const QChar *p = unicode();
+    uint64 val=0;
+    int l = length();
+    const uint64 max_mult = 1844674407370955161ULL;  // ULLONG_MAX/10, rounded down
+    bool is_ok = FALSE;
+    if ( !p )
+	goto bye;
+    while ( l && p->isSpace() )			// skip leading space
+	l--,p++;
+    if ( *p == '+' )
+	l--,p++;
+
+    // NOTE: toULong() code is similar
+    if ( !l || !ok_in_base(*p,base) )
+	goto bye;
+    while ( l && ok_in_base(*p,base) ) {
+	l--;
+	uint dv;
+	if ( p->isDigit() ) {
+	    dv = p->digitValue();
+	} else {
+	    if ( *p >= 'a' && *p <= 'z' )
+		dv = *p - 'a' + 10;
+	    else
+		dv = *p - 'A' + 10;
+	}
+	if ( val > max_mult || (val == max_mult && dv > (ULLONG_MAX%base)) )
+	    goto bye;
+	val = base*val + dv;
+	p++;
+    }
+
+    while ( l && p->isSpace() )			// skip trailing space
+	l--,p++;
+    if ( !l )
+	is_ok = TRUE;
+bye:
+    if ( ok )
+	*ok = is_ok;
+    return is_ok ? val : 0;
+}
+
+
+/*!
   Returns the string converted to a <code>short</code> value.
 
   If \a ok is non-null, \a *ok is set to TRUE if there are no
diff --git a/qtools/qstring.h b/qtools/qstring.h
index a64fabf..df3873d 100644
--- a/qtools/qstring.h
+++ b/qtools/qstring.h
@@ -463,6 +463,7 @@ public:
     uint	toUInt( bool *ok=0, int base=10 )	const;
     long	toLong( bool *ok=0, int base=10 )	const;
     ulong	toULong( bool *ok=0, int base=10 )	const;
+    uint64	toUInt64( bool *ok=0, int base=10 )	const;
     float	toFloat( bool *ok=0 )	const;
     double	toDouble( bool *ok=0 )	const;
 
diff --git a/src/util.cpp b/src/util.cpp
index d367c40..db6a19c 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -18,6 +18,7 @@
 #include <ctype.h>
 #include <errno.h>
 #include <math.h>
+#include <limits.h>
 
 #include "md5.h"
 
@@ -2472,6 +2473,35 @@ QCString fileToString(const char *name,bool filter,bool isSourceCode)
 QCString dateToString(bool includeTime)
 {
   QDateTime current = QDateTime::currentDateTime();
+  QCString sourceDateEpoch = portable_getenv("SOURCE_DATE_EPOCH");
+  if (!sourceDateEpoch.isEmpty())
+  {
+    bool ok;
+    uint64 epoch = sourceDateEpoch.toUInt64(&ok);
+    if (!ok)
+    {
+      static bool warnedOnce=FALSE;
+      if (!warnedOnce)
+      {
+        warn_uncond("Environment variable SOURCE_DATE_EPOCH does not contain a valid number; value is '%s'\n",
+            sourceDateEpoch.data());
+        warnedOnce=TRUE;
+      }
+    }
+    else if (epoch>UINT_MAX)
+    {
+      static bool warnedOnce=FALSE;
+      if (!warnedOnce)
+      {
+        warn_uncond("Environment variable SOURCE_DATA_EPOCH must have a value smaller than or equal to %llu; actual value %llu\n",UINT_MAX,epoch);
+        warnedOnce=TRUE;
+      }
+    }
+    else // all ok, replace current time with epoch value
+    {
+      current.setTime_t((ulong)epoch); // TODO: add support for 64bit epoch value
+    }
+  }
   return theTranslator->trDateTime(current.date().year(),
                                    current.date().month(),
                                    current.date().day(),