diff --git a/lib/xlsxio_read.c b/lib/xlsxio_read.c
index b1ccd26..42a9830 100644
--- a/lib/xlsxio_read.c
+++ b/lib/xlsxio_read.c
@@ -1264,10 +1264,12 @@ void data_sheet_expat_callback_value_data (void* callbackdata, const XML_Char* b
 {
   struct data_sheet_callback_data* data = (struct data_sheet_callback_data*)callbackdata;
   if (data->cell_string_type != none) {
-    if ((data->celldata = XML_Char_realloc(data->celldata, data->celldatalen + buflen + 1)) == NULL) {
+    XML_Char *temp = XML_Char_realloc(data->celldata, data->celldatalen + buflen + 1);
+    if (temp == NULL) {
       //memory allocation error
       data->celldatalen = 0;
     } else {
+      data->celldata = temp;
       //add new data to value buffer
       XML_Char_poscpy(data->celldata, data->celldatalen, buf, buflen);
       data->celldatalen += buflen;
diff --git a/lib/xlsxio_read_sharedstrings.c b/lib/xlsxio_read_sharedstrings.c
index b83de84..e59598f 100644
--- a/lib/xlsxio_read_sharedstrings.c
+++ b/lib/xlsxio_read_sharedstrings.c
@@ -195,10 +195,12 @@ void shared_strings_callback_find_shared_string_end (void* callbackdata, const X
 void shared_strings_callback_string_data (void* callbackdata, const XML_Char* buf, int buflen)
 {
   struct shared_strings_callback_data* data = (struct shared_strings_callback_data*)callbackdata;
-  if ((data->text = XML_Char_realloc(data->text, data->textlen + buflen)) == NULL) {
+  XML_Char *temp = XML_Char_realloc(data->text, data->textlen + buflen);
+  if (temp == NULL) {
     //memory allocation error
     data->textlen = 0;
   } else {
+    data->text = temp;
     XML_Char_poscpy(data->text, data->textlen, buf, buflen);
     data->textlen += buflen;
   }
diff --git a/lib/xlsxio_write.c b/lib/xlsxio_write.c
index 178873f..7175aa3 100644
--- a/lib/xlsxio_write.c
+++ b/lib/xlsxio_write.c
@@ -398,9 +398,12 @@ char* str_replace (char** s, size_t pos, size_t len, char* replacement)
     pos = totallen;
   if (pos + len > totallen)
     len = totallen - pos;
-  if (replacementlen > len)
-    if ((*s = (char*)realloc(*s, totallen - len + replacementlen + 1)) == NULL)
+  if (replacementlen > len) {
+    char *temp = (char*)realloc(*s, totallen - len + replacementlen + 1);
+    if (temp == NULL)
       return NULL;
+    *s = temp;
+  }
   memmove(*s + pos + replacementlen, *s + pos + len, totallen - pos - len + 1);
   memcpy(*s + pos, replacement, replacementlen);
   return *s;
@@ -484,8 +487,10 @@ int append_data (char** pdata, size_t* pdatalen, const char* format, ...)
   va_end(args);
   if (len < 0)
     return -1;
-  if ((*pdata = (char*)realloc(*pdata, *pdatalen + len + 1)) == NULL)
+  char *temp = (char*)realloc(*pdata, *pdatalen + len + 1);
+  if (temp == NULL)
     return -1;
+  *pdata = temp;
   va_start(args, format);
   vsnprintf(*pdata + *pdatalen, len + 1, format, args);
   va_end(args);
diff --git a/src/xlsxio_csv2xlsx.c b/src/xlsxio_csv2xlsx.c
index ecc5483..8d05028 100644
--- a/src/xlsxio_csv2xlsx.c
+++ b/src/xlsxio_csv2xlsx.c
@@ -36,8 +36,10 @@ THE SOFTWARE.
 int append_buffer_data (char** pdata, size_t* pdatalen, const char* bufferdata, size_t bufferdatalen)
 {
   //allocate larger data buffer, abort in case of memory allocation error
-  if ((*pdata = (char*)realloc(*pdata, *pdatalen + bufferdatalen + 1)) == NULL)
+  char *temp = (char*)realloc(*pdata, *pdatalen + bufferdatalen + 1);
+  if (temp == NULL)
     return 1;
+  *pdata = temp;
   //append new data and adjust length
   memcpy(*pdata + *pdatalen, bufferdata, bufferdatalen);
   *pdatalen += bufferdatalen;