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Gcc Error Attributes Are Not Allowed On A Function-definition

Note, for the MSP430 you can provide an argument to the interrupt attribute which specifies a name or number. interruptUse this attribute on the ARM, AVR, C4x, M32R/D and Xstormy16 ports to indicate that the specified function is an interrupt handler. GCC uses this information to improve pointer alignment analysis. This makes slightly better code. check over here

On SH2A targets, this attribute declares a function to be called using the TBR relative addressing mode. Note, on Epiphany targets, interrupts are enabled inside the function unless the disinterrupt attribute is also specified. The pointer name is formed by combining __imp_ and the function name. noreturnA few standard library functions, such as abort and exit, cannot return.

When casting a cube spell on a hex grid do you pick a honeycomb for origin or an intersection for origin? An alternative way to declare that a function does not return, which works in the current version and in some older versions, is as follows: typedef void voidfn (); volatile voidfn This is to allow easy merging of multiple compilation units into one, for example, by using the link-time optimization.

Note, interrupt handlers for the m68k, H8/300, H8/300H, H8S, and SH processors can be specified via the interrupt_handler attribute. With Epiphany targets it may also generate a special section with code to initialize the interrupt vector table. On systems that support the visibility attribute, this attribute also implies “default” visibility. The ISO C99 standard includes _Pragma, which now allows pragmas to be generated from macros.

On the SH Symbian OS target the dllimport attribute also has another affect—it can cause the vtable and run-time type information for a class to be exported. Beware that on some ELF systems this attribute is unsuitable for global functions in shared libraries with lazy binding (which is the default). This allows you to use them in header files without being concerned about a possible macro of the same name. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=12246 You can use __declspec(dllexport) as a synonym for __attribute__ ((dllexport)) for compatibility with other compilers.

error (" message ") If this attribute is used on a function declaration and a call to such a function is not eliminated through dead code elimination or other optimizations, an Currently, the attribute is ignored for inlined functions. The format-arg attribute allows you to identify your own functions which modify format strings, so that GCC can check the calls to printf, scanf, strftime or strfmon type function whose operands Such a function can be subject to common subexpression elimination and loop optimization just as an arithmetic operator would be.

Usually a good place to do the initialization is the startup routine. constMany functions do not examine any values except their arguments, and have no effects except the return value. On many systems, the linker is only able to arrange for functions to be aligned up to a certain maximum alignment. (For some linkers, the maximum supported alignment may be very Caveat: such addressing is by definition not position independent and hence this attribute must not be used for objects defined by shared libraries.

Lazy binding will send the first call via resolving code in the loader, which might assume EAX, EDX and ECX can be clobbered, as per the standard calling conventions. You must use GAS and GLD from GNU binutils version 2.7 or later for this attribute to work correctly. naked This attribute is available on the ARM, AVR, MCORE, MSP430, NDS32, RL78, RX and SPU ports. See also the interrupt function attribute.

For example, most functions in the standard C library can be guaranteed not to throw an exception with the notable exceptions of qsort and bsearch that take function pointer arguments. The use of the dllimport attribute on imported variables was required on older versions of GNU ld, but can now be avoided by passing the --enable-auto-import switch to ld. It is up to the user to make sure that a function is only invoked on a machine that supports the particular ISA it is compiled for (for example by using In the example above, the format string (my_format) is the second argument of the function my_print, and the arguments to check start with the third argument, so the correct parameters for

Join them; it only takes a minute: Sign up gcc attributes with C++ methods up vote 6 down vote favorite In GCC with a C++ method defined in a header file, The attribute is also overridden by a subsequent declaration as dllexport . Therefore you need to ensure that all the special page vector routines should get mapped within the address range 0x0F0000 to 0x0FFFFF (for M16C) and 0xFF0000 to 0xFFFFFF (for M32C).

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protectedProtected visibility indicates that the symbol will be placed in the dynamic symbol table, but that references within the defining module will bind to the local symbol. The long_call attribute causes the compiler to always call the function by first loading its address into a register and then using the contents of that register. You may provide an optional integer priority to control the order in which constructor and destructor functions are run. Unsubstantiated How to handle a senior developer diva who seems unaware that his skills are obsolete?

The definition in the header file causes most calls to the function to be inlined. The long_call attribute causes the compiler to always call the function by first loading its address into a register and then using the contents of that register. alias ("target")The alias attribute causes the declaration to be emitted as an alias for another symbol, which must be specified. This keyword is followed by an attribute specification inside double parentheses.

If callee is responsible for popping the hidden pointer, specify number equal to one. It may indeed be the only way, but that sure would be a mighty unlikely situation... –Brian Knoblauch Nov 2 '11 at 12:21 @MetallicPriest, so you are asking the This attribute overrides the -mips16 and -mmicromips options on the command line (see MIPS Options ). Not all target machines support this attribute.

The compiler will generate more efficient code for certain operations on data in the eight bit data area. As with functions, using the attribute for a variable eliminates a thunk in the DLL. share|improve this answer answered Nov 2 '11 at 12:00 Basile Starynkevitch 123k895202 add a comment| Not the answer you're looking for? Both attributes override the `-mlong-calls' (@xref{ARM Options}) command line switch and #pragma long_calls settings.

The parameter archetype determines how the format string is interpreted, and should be printf, scanf, strftime or strfmon. (You can also use __printf__, __scanf__, __strftime__ or __strfmon__.) The parameter string-index specifies The short_call attribute always places the offset to the function from the call site into the ‘ BL ’ instruction directly. In C++, this attribute does not depend on extern in any way, but it still requires the inline keyword to enable its special behavior. However, it has been found convenient to use __attribute__ to achieve a natural attachment of attributes to their corresponding declarations, whereas #pragma GCC is of use for constructs that do not

It represents a function, which is called by the exception handling mechanism if an exception occurs. At the end of a function, it will jump to a board-specific routine instead of using rts. You must use GAS and GLD from GNU binutils version 2.7 or later for this attribute to work correctly. The following code does not work: class foo { public: void my_func() __attribute__((hot)); void my_func() { // Some stuff } }; It seems like you have to put the attributes in

void __attribute__ ((visibility ("protected"))) f () { /* Do something. */; } int i __attribute__ ((visibility ("hidden"))); See the ELF gABI for complete details, but the short story is: defaultDefault visibility See section 5.26 Attribute Syntax, for details of the exact syntax for using attributes.