Preprocessor regression in build 3950
There is a dedicated thread for this build: MetaTrader 5 Platform Build 3950: Deposits/withdrawals in the terminal and updated trading report
In the future, please search before posting and do so in the appropriate thread or section.
EDIT: I have placed a "pocket" reference of your post in the thread I mentioned above.
The issue has already been reported, so please read the following posts related to the use of the "##" combining operator in macros:
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There appears to be a regression in build 3950 (14 Sep 2023) in the behavior of the preprocessor. The code below compiles without errors on the old build 3802 (9 Jun 2023):
#define NAME(prefix, linenr) prefix##linenr
#define MAKE_VAR \
int NAME(example, __LINE__) = 123
void OnStart() {
MAKE_VAR; // int example6 = 123;
MAKE_VAR; // int example7 = 123;
}
However, when compiling this same code in build 3950, I get an error message:
'example__LINE__' - variable already defined
see declaration of variable '"void OnStart()"::example__LINE__'
Unfortunately, I use preprocessor concatenation ## a lot in my code so all my experts and indicators are now broken and don't compile anymore...
I filed a bug report here: https://www.mql5.com/en/forum/628/page112#comment_49409863 (because Service Desk chat-bot did not understand me and was not filing a bug)