Atmel CAVR-4 Manuale Utente

CAVR-4

Part 2. Compiler reference

#pragma diag_warning

#pragma diag_warning=tag,tag,...

Changes the severity level to 

warning

 for the specified diagnostics. For example:

#pragma diag_warning=Pe826

See the chapter Diagnostics for more information about diagnostic messages.

#pragma include_alias

#pragma include_alias "orig_header" "subst_header"

#pragma include_alias <orig_header> <subst_header>

The 

#pragma

 

include_alias

 directive makes it possible to provide an alias for a 

header file. This is useful for substituting one header file with another, and for 
specifying an absolute path to a relative file.

The parameter 

 is used for specifying an alias for 

. This 

pragma directive must appear before the corresponding 

#include

 directives and 

subst_header

 must match its corresponding 

#include

 directive exactly.

#pragma include_alias <stdio.h> <C:\MyHeaders\stdio.h>

#include <stdio.h>

This example will substitute the relative file 

stdio.h

 with a counterpart located 

according to the specified path.

#pragma inline

#pragma inline[=forced]

The 

#pragma

 

inline

 directive advises the compiler that the function whose 

declaration follows immediately after the directive should be inlined—that is, expanded 
into the body of the calling function. Whether the inlining actually takes place is subject 
to the compiler’s heuristics.

This is similar to the C++ keyword 

inline

, but has the advantage of being available in 

C code.

Specifying 

#pragma inline=forced

 disables the compiler’s heuristics and forces the 

inlining. If the inlining fails for some reason, for example if it cannot be used with the 
function type in question (like 

printf

), an error message is emitted.