diff --git a/mozilla/base/src/nsString2.cpp b/mozilla/base/src/nsString2.cpp
index 5d5ed3836b5..9263c5883f6 100644
--- a/mozilla/base/src/nsString2.cpp
+++ b/mozilla/base/src/nsString2.cpp
@@ -829,8 +829,8 @@ nsString2& nsString2::Append(const char* aCString,PRInt32 aCount) {
     nsStr temp;
     Initialize(temp,eOneByte);
     temp.mStr=(char*)aCString;
-    temp.mLength=nsCRT::strlen(aCString);
-    if(-1==aCount) aCount=temp.mLength;
+    if(-1==aCount) aCount= nsCRT::strlen(aCString);
+    temp.mLength = aCount;
     nsStr::Append(*this,temp,0,aCount,mAgent);
   }
   return *this;
@@ -848,8 +848,8 @@ nsString2& nsString2::Append(const PRUnichar* aString,PRInt32 aCount) {
     nsStr temp;
     Initialize(temp,eTwoByte);
     temp.mUStr=(PRUnichar*)aString;
-    temp.mLength=nsCRT::strlen(aString);
-    if(-1==aCount) aCount=temp.mLength;
+    if(-1==aCount) aCount= nsCRT::strlen(aString);
+    temp.mLength = aCount;
     nsStr::Append(*this,temp,0,aCount,mAgent);
   }
   return *this;
diff --git a/mozilla/string/obsolete/nsString2.cpp b/mozilla/string/obsolete/nsString2.cpp
index 5d5ed3836b5..9263c5883f6 100644
--- a/mozilla/string/obsolete/nsString2.cpp
+++ b/mozilla/string/obsolete/nsString2.cpp
@@ -829,8 +829,8 @@ nsString2& nsString2::Append(const char* aCString,PRInt32 aCount) {
     nsStr temp;
     Initialize(temp,eOneByte);
     temp.mStr=(char*)aCString;
-    temp.mLength=nsCRT::strlen(aCString);
-    if(-1==aCount) aCount=temp.mLength;
+    if(-1==aCount) aCount= nsCRT::strlen(aCString);
+    temp.mLength = aCount;
     nsStr::Append(*this,temp,0,aCount,mAgent);
   }
   return *this;
@@ -848,8 +848,8 @@ nsString2& nsString2::Append(const PRUnichar* aString,PRInt32 aCount) {
     nsStr temp;
     Initialize(temp,eTwoByte);
     temp.mUStr=(PRUnichar*)aString;
-    temp.mLength=nsCRT::strlen(aString);
-    if(-1==aCount) aCount=temp.mLength;
+    if(-1==aCount) aCount= nsCRT::strlen(aString);
+    temp.mLength = aCount;
     nsStr::Append(*this,temp,0,aCount,mAgent);
   }
   return *this;
diff --git a/mozilla/xpcom/ds/nsString2.cpp b/mozilla/xpcom/ds/nsString2.cpp
index 5d5ed3836b5..9263c5883f6 100644
--- a/mozilla/xpcom/ds/nsString2.cpp
+++ b/mozilla/xpcom/ds/nsString2.cpp
@@ -829,8 +829,8 @@ nsString2& nsString2::Append(const char* aCString,PRInt32 aCount) {
     nsStr temp;
     Initialize(temp,eOneByte);
     temp.mStr=(char*)aCString;
-    temp.mLength=nsCRT::strlen(aCString);
-    if(-1==aCount) aCount=temp.mLength;
+    if(-1==aCount) aCount= nsCRT::strlen(aCString);
+    temp.mLength = aCount;
     nsStr::Append(*this,temp,0,aCount,mAgent);
   }
   return *this;
@@ -848,8 +848,8 @@ nsString2& nsString2::Append(const PRUnichar* aString,PRInt32 aCount) {
     nsStr temp;
     Initialize(temp,eTwoByte);
     temp.mUStr=(PRUnichar*)aString;
-    temp.mLength=nsCRT::strlen(aString);
-    if(-1==aCount) aCount=temp.mLength;
+    if(-1==aCount) aCount= nsCRT::strlen(aString);
+    temp.mLength = aCount;
     nsStr::Append(*this,temp,0,aCount,mAgent);
   }
   return *this;
diff --git a/mozilla/xpcom/string/obsolete/nsString2.cpp b/mozilla/xpcom/string/obsolete/nsString2.cpp
index 5d5ed3836b5..9263c5883f6 100644
--- a/mozilla/xpcom/string/obsolete/nsString2.cpp
+++ b/mozilla/xpcom/string/obsolete/nsString2.cpp
@@ -829,8 +829,8 @@ nsString2& nsString2::Append(const char* aCString,PRInt32 aCount) {
     nsStr temp;
     Initialize(temp,eOneByte);
     temp.mStr=(char*)aCString;
-    temp.mLength=nsCRT::strlen(aCString);
-    if(-1==aCount) aCount=temp.mLength;
+    if(-1==aCount) aCount= nsCRT::strlen(aCString);
+    temp.mLength = aCount;
     nsStr::Append(*this,temp,0,aCount,mAgent);
   }
   return *this;
@@ -848,8 +848,8 @@ nsString2& nsString2::Append(const PRUnichar* aString,PRInt32 aCount) {
     nsStr temp;
     Initialize(temp,eTwoByte);
     temp.mUStr=(PRUnichar*)aString;
-    temp.mLength=nsCRT::strlen(aString);
-    if(-1==aCount) aCount=temp.mLength;
+    if(-1==aCount) aCount= nsCRT::strlen(aString);
+    temp.mLength = aCount;
     nsStr::Append(*this,temp,0,aCount,mAgent);
   }
   return *this;