🐛 Fix M105 (MString append TS) and EEPROM ver

Followup to #24390

Marlin/src/core/mstring.h

@@ -112,10 +112,9 @@ public:
   MString& set(const char *s)             { return set(const_cast<char*>(s)); }
   MString& set_P(PGM_P const s)           { strncpy_P(str, s, SIZE);                  debug(F("pstring")); return *this; }
   MString& set(FSTR_P const f)            { return set_P(FTOP(f)); }
-  MString& set(const MString &s)          { strncpy(str, s.str, SIZE);                debug(F("MString")); return *this; }
   MString& set(const bool &b)             { return set(b ? F("true") : F("false")); }
   MString& set(const char c)              { str[0] = c; if (1 < SIZE) str[1] = '\0';  debug(F("char"));    return *this; }
-  MString& set(const int8_t &i)           { SNPRINTF_P(str, SIZE, PSTR("%d"),  i);    debug(F("int8_t"));   return *this; }
+  MString& set(const int8_t &i)           { SNPRINTF_P(str, SIZE, PSTR("%d"),  i);    debug(F("int8_t"));  return *this; }
   MString& set(const short &i)            { SNPRINTF_P(str, SIZE, PSTR("%d"),  i);    debug(F("short"));   return *this; }
   MString& set(const int &i)              { SNPRINTF_P(str, SIZE, PSTR("%d"),  i);    debug(F("int"));     return *this; }
   MString& set(const long &l)             { SNPRINTF_P(str, SIZE, PSTR("%ld"), l);    debug(F("long"));    return *this; }
@@ -130,6 +129,9 @@ public:
   MString& set(const xyz_pos_t &v)        { set(); return append(v); }
   MString& set(const xyze_pos_t &v)       { set(); return append(v); }
 
+  template <int S>
+  MString& set(const MString<S> &m)       { strncpy(str, &m, SIZE); debug(F("MString")); return *this; }
+
   MString& setn(char *s, int len)         { int c = _MIN(len, SIZE); strncpy(str, s, c); str[c] = '\0'; debug(F("string")); return *this; }
   MString& setn(const char *s, int len)   { return setn(const_cast<char*>(s), len); }
   MString& setn_P(PGM_P const s, int len) { int c = _MIN(len, SIZE); strncpy_P(str, s, c); str[c] = '\0'; debug(F("pstring")); return *this; }
@@ -157,7 +159,6 @@ public:
   MString& append(const char *s)              { return append(const_cast<char *>(s)); }
   MString& append_P(PGM_P const s)            { int sz = length(); if (sz < SIZE) strncpy_P(str + sz, s, SIZE - sz); debug(F("pstring")); return *this; }
   MString& append(FSTR_P const f)             { return append_P(FTOP(f)); }
-  MString& append(const MString &s)           { return append(s.str); }
   MString& append(const bool &b)              { return append(b ? F("true") : F("false")); }
   MString& append(const char c)               { int sz = length(); if (sz < SIZE) { str[sz] = c; if (sz < SIZE - 1) str[sz + 1] = '\0'; } return *this; }
   #if ENABLED(FASTER_APPEND)
@@ -186,6 +187,9 @@ public:
   MString& append(const xyz_pos_t &v)         { LOOP_NUM_AXES(i)     { if (i) append(' '); append(AXIS_CHAR(i), v[i]); } debug(F("xyz")); return *this; }
   MString& append(const xyze_pos_t &v)        { LOOP_LOGICAL_AXES(i) { if (i) append(' '); append(AXIS_CHAR(i), v[i]); } debug(F("xyze")); return *this; }
 
+  template<int S>
+  MString& append(const MString<S> &m)        { return append(&m); }
+
   // Append only if the given space is available
   MString& appendn(char *s, int len)          { int sz = length(), c = _MIN(len, SIZE - sz); if (c > 0) { strncpy(str + sz, s, c); str[sz + c] = '\0'; } debug(F("string")); return *this; }
   MString& appendn(const char *s, int len)    { return appendn(const_cast<char *>(s), len); }
@@ -227,7 +231,7 @@ public:
   MString(T arg1, Args... more)           { set(arg1); append(more...); }
 
   // Catch unhandled types to prevent infinite recursion
-  template<typename T> MString& append(T) { return append('?'); }
+  template<typename T> MString& append(T) { return append(TERN(MSTRING_DEBUG, typeid(T).name(), '?')); }
 
   // Take a list of any number of arguments and append them to the string
   template<typename T, typename... Args>
@@ -313,4 +317,5 @@ public:
 #ifndef TS_SIZE
   #define TS_SIZE 63
 #endif
-#define TS(V...) MString<TS_SIZE>(V)
+typedef MString<TS_SIZE, DISABLED(UNSAFE_MSTRING)> TString;
+#define TS(V...) TString(V)

Marlin/src/module/settings.cpp

@@ -814,14 +814,14 @@ void MarlinSettings::postprocess() {
    */
   bool MarlinSettings::save() {
     float dummyf = 0;
-    MString<4> ver(F("ERR"));
+    MString<3> ver(F("ERR"));
 
     if (!EEPROM_START(EEPROM_OFFSET)) return false;
 
     EEPROM_Error eeprom_error = ERR_EEPROM_NOERR;
 
     // Write or Skip version. (Flash doesn't allow rewrite without erase.)
-    TERN(FLASH_EEPROM_EMULATION, EEPROM_SKIP, EEPROM_WRITE)(&ver);
+    TERN(FLASH_EEPROM_EMULATION, EEPROM_SKIP, EEPROM_WRITE)(ver);
 
     #if ENABLED(EEPROM_INIT_NOW)
       EEPROM_SKIP(build_hash);  // Skip the hash slot which will be written later

Marlin/src/module/temperature.cpp

@@ -4185,7 +4185,7 @@ void Temperature::isr() {
 
     SString<50> s(' ', k);
     if (TERN0(HAS_MULTI_HOTEND, e >= 0)) s += char('0' + e);
-    s += TS(':', p_float_t(c, SFP));
+    s += ':'; s += p_float_t(c, SFP);
     if (show_t) { s += F(" /"); s += p_float_t(t, SFP); }
     #if ENABLED(SHOW_TEMP_ADC_VALUES)
       // Temperature MAX SPI boards do not have an OVERSAMPLENR defined