linux PIString fix

libs/main/core/pistring.cpp

@@ -234,19 +234,19 @@ void PIString::appendFromChars(const char * c, int s, const char * codepage) {
 	mbstate_t state;
 	memset(&state, 0, sizeof(state));
 	const char ** pc;
-	const char * cc_;
+	char * c_ = nullptr;
 	if (s > 0) {
-		char c_ [s+1];
+		c_ = malloc(s+1);
 		memcpy(c_, c, s);
 		c_[s] = '\0';
-		cc_ = &c_[0];
-		pc = &cc_;
+		pc = &c_;
 	} else {
 		pc = &c;
 	}
 	size_t len = mbsrtowcs(NULL, pc, 0, &state);
 	wchar_t wstr[len+1];
 	mbsrtowcs(&wstr[0], pc, len+1, &state);
+	if (s > 0) free(c_);
 	enlarge(len);
 	for (size_t i=0; i<len; ++i) (*this)[old_sz+i] = wstr[i];
 //	//qDebug() << "FromChars done" << size();