Identifiers for Delphi's $WARN compiler directive

Question

Delphi has a $WARN compiler directive that allows one to selectively enable or disable specific warnings. The Delphi 2009 help file describes the syntax:

{$WARN identifier ON|OFF}

But it only lists the identifiers for 6 warnings.

I'd like to have a complete list of all the warning identifiers. In particular, I want to know the identifiers for the implicit string cast warnings W1057 and W1058 in Delphi 2009.

I managed to guess the one for implicit Ansi->Unicode casts (W1057):

{$WARN IMPLICIT_STRING_CAST OFF}

Googling for that found me the other one:

{$WARN IMPLICIT_STRING_CAST_LOSS OFF}

Though that solves my immediate need, I'd still like to know the complete list of warning identifiers. Stuff like this should be documented.

Answer 1

I looked through the help and didn't see a full list...so poking around the code it appears the compiler warning constants are all listed in: CodeGear\RAD Studio\6.0\sources\toolsapi\DCCStrs.pas

Search for "Implicit_String_Cast_Loss" and you'll see the constant sIMPLICIT_STRING_CAST_LOSS = 'DCC_IMPLICIT_STRING_CAST_LOSS';

I would assume the rest of the DCC_xxx strings with corresponding X_true/_false/_error defines are what you are after.

Online help hasn't been very good since Delphi 7.

Answer 2

Something else not mentioned in the Delphi 2009 documentation:

The $WARN directive now has a 3rd option ERROR in addition to ON and OFF. So you can have:

{$WARN IMPLICIT_STRING_CAST OFF} to disable the warning
{$WARN IMPLICIT_STRING_CAST ON} to enable warning
{$WARN IMPLICIT_STRING_CAST ERROR} to turn the warning into an error

Answer 3

Stuff like this should be documented

As of today, the full list of identifiers and their compiler warning numbers are listed in the documentation at:

http://docwiki.embarcadero.com/RADStudio/en/Warning_messages_(Delphi)

Excerpt:

The identifier in the $WARN directive can have any of the following values:

|      Warning      | Identifier |
|:-----------------:|:----------:|
| SYMBOL_DEPRECATED | W1000      |
| SYMBOL_LIBRARY    | W1001      |
| (...)             | (...)      |