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 unsigned long

+  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 short 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(),