Unwanted W8080 warnings from TeeChart component in CBuilder XE8

Question

When compiling a project under CBuilder XE8 that uses the TeeChart components distributed with that IDE, I get long reams of errors like this:

[bcc32 Warning] GdiplusStringFormat.h(306): W8058 Cannot create pre-compiled header: initialized data in header
[bcc32 Warning] MI3Proc.cpp(719): W8080 'Gdiplus::FlatnessDefault' is declared but never used
[bcc32 Warning] MI3Proc.cpp(719): W8080 'Gdiplus::GenericSansSerifFontFamily' is declared but never used
[bcc32 Warning] MI3Proc.cpp(719): W8080 'Gdiplus::GenericSerifFontFamily' is declared but never used
[bcc32 Warning] MI3Proc.cpp(719): W8080 'Gdiplus::GenericMonospaceFontFamily' is declared but never used
[bcc32 Warning] MI3Proc.cpp(719): W8080 'Gdiplus::GenericSansSerifFontFamilyBuffer' is declared but never used
[bcc32 Warning] MI3Proc.cpp(719): W8080 'Gdiplus::GenericSerifFontFamilyBuffer' is declared but never used
[bcc32 Warning] MI3Proc.cpp(719): W8080 'Gdiplus::GenericMonospaceFontFamilyBuffer' is declared but never used
[bcc32 Warning] MI3Proc.cpp(719): W8080 'Gdiplus::GenericTypographicStringFormatBuffer' is declared but never used
[bcc32 Warning] MI3Proc.cpp(719): W8080 'Gdiplus::GenericDefaultStringFormatBuffer' is declared but never used

This problem is also reported on Steema's support forum at http://www.teechart.net/support/viewtopic.php?f=3&t=15374, but there is no followup.

I had a similar issue with TeeChart under CBuilder 4 (something like 20 years ago!). Hmmm.

I don't want to turn off the W8080 warning project-wide, as it helps keep my code clean, but is there any way to turn off the warnings just for the TeeChart unit?

Additionally, I'm not sure what to make of the W8058 error. The #pragma hdrstop precedes the include of VclTee.TeeGDIPlus.hpp, so this error should not be occurring.

EDIT: Some more information I've discovered is that the offending variables are static/const global variable declared and initialized in GdiplusEnums.h and GdiplusHeaders.h (files copyright 2001 by Microsoft).

Temporarily disabling the 8080 warning does not work because somewhere in the chain of nested includes, the 8080 warning is reset to default. If you disable the 8080 warning in the call to the compiler (i.e. global options), then all 8080 warnings will cease, but then you don't catch your own mistakes. Even putting the entire cpp unit in a #pragma warn -8080 block will not stop the warnings!

The only way I've found to stop the warnings (without globally disabling the 8080 warning) is to put dummy code like this somewhere in each affected source unit (so that the variables are referenced).

   void           *pvDummy;
   double         dDummy;
   BYTE           *pBYTEDummy;

   dDummy = Gdiplus::FlatnessDefault;
   pvDummy = Gdiplus::GenericSansSerifFontFamily;
   pvDummy = Gdiplus::GenericSerifFontFamily;
   pvDummy = Gdiplus::GenericMonospaceFontFamily;
   pBYTEDummy = Gdiplus::GenericSansSerifFontFamilyBuffer;
   pBYTEDummy = Gdiplus::GenericSerifFontFamilyBuffer;
   pBYTEDummy = Gdiplus::GenericMonospaceFontFamilyBuffer;
   pBYTEDummy = Gdiplus::GenericTypographicStringFormatBuffer;
   pBYTEDummy = Gdiplus::GenericDefaultStringFormatBuffer;

The method containing this code has to be in a #pragma warn -8004 block to avoid warnings about "xxx is assigned a value that is never used". Grrr.

This does offend some sense of good coding style, but there you go...

Answer 1

You can disable the W8080 (or any other warning) using the #pragma warn directive.

I would add it before the header that produces the warnings, so you don't modify the header. For example:

#pragma warn -8080
#include <TheOffendingHeader.h>
#pragma warn .8080