diff --git a/source/blender/datatoc/datatoc.c b/source/blender/datatoc/datatoc.c
index 379658bb4c4..236d9af8ef1 100644
--- a/source/blender/datatoc/datatoc.c
+++ b/source/blender/datatoc/datatoc.c
@@ -51,6 +51,7 @@ int main(int argc, char **argv)
 	FILE *fpin,  *fpout;
 	long size;
 	int i;
+	int argv_len;
 
 	if (argc < 2) {
 		printf("Usage: datatoc <data_file_from> <data_file_to>\n");
@@ -75,7 +76,8 @@ int main(int argc, char **argv)
 	printf("Making C file <%s>\n", argv[2]);
 #endif
 
-	for (i = 0; i < (int)strlen(argv[1]); i++)
+	argv_len = (int)strlen(argv[1]);
+	for (i = 0; i < argv_len; i++)
 		if (argv[1][i] == '.') argv[1][i] = '_';
 
 	fpout = fopen(argv[2], "w");
diff --git a/source/blender/editors/interface/interface_handlers.c b/source/blender/editors/interface/interface_handlers.c
index 4f6e184dceb..531fbec4cc3 100644
--- a/source/blender/editors/interface/interface_handlers.c
+++ b/source/blender/editors/interface/interface_handlers.c
@@ -1674,10 +1674,11 @@ static int ui_textedit_copypaste(uiBut *but, uiHandleButtonData *data, int paste
 {
 	char buf[UI_MAX_DRAW_STR] = {0};
 	char *str, *p, *pbuf;
-	int len, x, i, changed = 0;
+	int x, changed = 0;
+	int str_len, buf_len;
 
 	str = data->str;
-	len = strlen(str);
+	str_len = strlen(str);
 	
 	/* paste */
 	if (paste) {
@@ -1687,28 +1688,28 @@ static int ui_textedit_copypaste(uiBut *but, uiHandleButtonData *data, int paste
 
 		if (p && p[0]) {
 			unsigned int y;
-			i = 0;
-			while (*p && *p != '\r' && *p != '\n' && i < UI_MAX_DRAW_STR - 1) {
-				buf[i++] = *p;
+			buf_len = 0;
+			while (*p && *p != '\r' && *p != '\n' && buf_len < UI_MAX_DRAW_STR - 1) {
+				buf[buf_len++] = *p;
 				p++;
 			}
-			buf[i] = 0;
+			buf[buf_len] = 0;
 
 			/* paste over the current selection */
 			if ((but->selend - but->selsta) > 0) {
 				ui_textedit_delete_selection(but, data);
-				len = strlen(str);
+				str_len = strlen(str);
 			}
 			
-			for (y = 0; y < strlen(buf); y++) {
+			for (y = 0; y < buf_len; y++) {
 				/* add contents of buffer */
-				if (len + 1 < data->maxlen) {
+				if (str_len + 1 < data->maxlen) {
 					for (x = data->maxlen; x > but->pos; x--)
 						str[x] = str[x - 1];
 					str[but->pos] = buf[y];
 					but->pos++; 
-					len++;
-					str[len] = '\0';
+					str_len++;
+					str[str_len] = '\0';
 				}
 			}
 
diff --git a/source/blender/editors/space_text/text_ops.c b/source/blender/editors/space_text/text_ops.c
index 83a1bfee0d8..71044579df4 100644
--- a/source/blender/editors/space_text/text_ops.c
+++ b/source/blender/editors/space_text/text_ops.c
@@ -1131,21 +1131,20 @@ static int text_convert_whitespace_exec(bContext *C, wmOperator *op)
 	TextLine *tmp;
 	FlattenString fs;
 	size_t a, j;
-	char *text_check_line, *new_line;
+	char *new_line;
 	int extra, number; //unknown for now
 	int type = RNA_enum_get(op->ptr, "type");
-	
-	tmp = text->lines.first;
-	
+
 	/* first convert to all space, this make it a lot easier to convert to tabs
 	 * because there is no mixtures of ' ' && '\t' */
-	while (tmp) {
-		text_check_line = tmp->line;
+	for (tmp = text->lines.first; tmp; tmp = tmp->next) {
+		const char *text_check_line     = tmp->line;
+		const int   text_check_line_len = tmp->len;
 		number = flatten_string(st, &fs, text_check_line) + 1;
 		flatten_string_free(&fs);
 		new_line = MEM_callocN(number, "Converted_Line");
 		j = 0;
-		for (a = 0; a < strlen(text_check_line); a++) { //foreach char in line
+		for (a = 0; a < text_check_line_len; a++) { //foreach char in line
 			if (text_check_line[a] == '\t') { //checking for tabs
 				//get the number of spaces this tabs is showing
 				//i don't like doing it this way but will look into it later
@@ -1175,20 +1174,19 @@ static int text_convert_whitespace_exec(bContext *C, wmOperator *op)
 		tmp->line = new_line;
 		tmp->len = strlen(new_line);
 		tmp->format = NULL;
-		tmp = tmp->next;
 	}
 	
 	if (type == TO_TABS) { // Converting to tabs
 		//start over from the beginning
-		tmp = text->lines.first;
 		
-		while (tmp) {
-			text_check_line = tmp->line;
+		for (tmp = text->lines.first; tmp; tmp = tmp->next) {
+			const char *text_check_line     = tmp->line;
+			const int   text_check_line_len = tmp->len;
 			extra = 0;
-			for (a = 0; a < strlen(text_check_line); a++) {
+			for (a = 0; a < text_check_line_len; a++) {
 				number = 0;
 				for (j = 0; j < (size_t)st->tabnumber; j++) {
-					if ((a + j) <= strlen(text_check_line)) { //check to make sure we are not pass the end of the line
+					if ((a + j) <= text_check_line_len) { //check to make sure we are not pass the end of the line
 						if (text_check_line[a + j] != ' ') {
 							number = 1;
 						}
@@ -1201,12 +1199,12 @@ static int text_convert_whitespace_exec(bContext *C, wmOperator *op)
 			}
 			
 			if (extra > 0) {   //got tabs make malloc and do what you have to do
-				new_line = MEM_callocN(strlen(text_check_line) - (((st->tabnumber * extra) - extra) - 1), "Converted_Line");
+				new_line = MEM_callocN(text_check_line_len - (((st->tabnumber * extra) - extra) - 1), "Converted_Line");
 				extra = 0; //reuse vars
-				for (a = 0; a < strlen(text_check_line); a++) {
+				for (a = 0; a < text_check_line_len; a++) {
 					number = 0;
 					for (j = 0; j < (size_t)st->tabnumber; j++) {
-						if ((a + j) <= strlen(text_check_line)) { //check to make sure we are not pass the end of the line
+						if ((a + j) <= text_check_line_len) { //check to make sure we are not pass the end of the line
 							if (text_check_line[a + j] != ' ') {
 								number = 1;
 							}
@@ -1233,7 +1231,6 @@ static int text_convert_whitespace_exec(bContext *C, wmOperator *op)
 				tmp->len = strlen(new_line);
 				tmp->format = NULL;
 			}
-			tmp = tmp->next;
 		}
 	}
 
diff --git a/source/blender/makesdna/intern/makesdna.c b/source/blender/makesdna/intern/makesdna.c
index fa0b313a120..e02a9bfe56a 100644
--- a/source/blender/makesdna/intern/makesdna.c
+++ b/source/blender/makesdna/intern/makesdna.c
@@ -984,7 +984,7 @@ static int make_structDNA(char *baseDirectory, FILE *file)
 	/* little test first...                                                  */
 	/* Mind the breaking condition here!                                     */
 	if (debugSDNA) printf("\tStart of header scan:\n"); 
-	for (i = 0; strlen(includefiles[i]); i++) {
+	for (i = 0; *(includefiles[i]) != '\0'; i++) {
 		sprintf(str, "%s%s", baseDirectory, includefiles[i]);
 		if (debugSDNA) printf("\t|-- Converting %s\n", str);
 		if (convert_include(str)) {
@@ -1100,7 +1100,7 @@ static int make_structDNA(char *baseDirectory, FILE *file)
 			else {
 
 				/* add all include files defined in the global array */
-				for (i = 0; strlen(includefiles[i]); i++) {
+				for (i = 0; *(includefiles[i]) != '\0'; i++) {
 					fprintf(fp, "#include \"%s%s\"\n", baseDirectory, includefiles[i]);
 				}