Fix data race when threads raise an error msg at the same time

src/common/GmshMessage.cpp

@@ -480,6 +480,8 @@ std::string Msg::PrintResources(bool printDate, bool printWallTime,
 }
 
 void Msg::Error(const char *fmt, ...)
+{
+#pragma omp critical(MsgError)
   {
     _errorCount++;
     _atLeastOneErrorInRun = 1;
@@ -534,8 +536,11 @@ void Msg::Error(const char *fmt, ...)
       Exit(1);
     }
   }
+}
 
 void Msg::Warning(const char *fmt, ...)
+{
+#pragma omp critical(MsgWarning)
   {
     _warningCount++;
 
@@ -575,11 +580,13 @@ void Msg::Warning(const char *fmt, ...)
       fflush(stderr);
     }
   }
+}
 
 void Msg::Info(const char *fmt, ...)
 {
   if(GetVerbosity() < 4) return;
-
+#pragma omp critical(MsgInfo)
+  {
     char str[5000];
     va_list args;
     va_start(args, fmt);
@@ -617,6 +624,7 @@ void Msg::Info(const char *fmt, ...)
       fflush(stdout);
     }
   }
+}
 
 void Msg::RequestRender()
 {