pru: Document that arguments are not passed to main with -minrt

The minimal runtime has been documented from the beginning to break some
standard features in order to reduce code size, while keeping
the features required by typical firmware programs.  Document one more
imposed restriction - the main() function must take no arguments.

gcc/ChangeLog:

	* doc/invoke.texi (-minrt): Clarify that main
	must take no arguments.

Signed-off-by: Dimitar Dimitrov <dimitar@dinux.eu>
This commit is contained in:
Dimitar Dimitrov 2024-02-01 19:19:54 +02:00
parent c0a80af4a1
commit e3dfc15051

View file

@ -30091,11 +30091,18 @@ These command-line options are defined for PRU target:
@table @gcctabopt
@opindex minrt
@item -minrt
Link with a minimum runtime environment, with no support for static
initializers and constructors. Using this option can significantly reduce
the size of the final ELF binary. Beware that the compiler could still
generate code with static initializers and constructors. It is up to the
programmer to ensure that the source program will not use those features.
Link with a minimum runtime environment. This can significantly reduce
the size of the final ELF binary, but some standard C runtime features
are removed.
This option disables support for static initializers and constructors.
Beware that the compiler could still generate code with static initializers
and constructors. It is up to the programmer to ensure that the source
program will not use those features.
The minimal startup code would not pass @code{argc} and @code{argv} arguments
to @code{main}, so the latter must be declared as @code{int main (void)}.
This is already the norm for most firmware projects.
@opindex mmcu
@item -mmcu=@var{mcu}