Quality RTOS & Embedded Software

 Real time embedded FreeRTOS RSS feed 
Quick Start Supported MCUs PDF Books Trace Tools Ecosystem


FreeRTOS 4.0.4, GCC: Inlining

Posted by Thomas K.-H. Nittel on July 19, 2006

when the module FreeRTOSV4.0.4\FreeRTOS\Source\portable\GCC\ARM7_AT91SAM7S\portISR.c is compiled with arm-elf-gcc 4.1.0 the following warning appears
Source/portable/GCC/ARM7_AT91SAM7S/portISR.c -o portISR.o
../../Source/FreeRTOS_4.0.4/Source/portable/GCC/ARM7_AT91SAM7S/portISR.c: In function 'vPreemptiveTick':
../../Source/FreeRTOS_4.0.4/Source/include/task.h:832: warning: inlining failed in call to 'vTaskIncrementTick': function body not available
../../Source/FreeRTOS_4.0.4/Source/portable/GCC/ARM7_AT91SAM7S/portISR.c:144: warning: called from here

Obviously inlining doesn't work with GCC.

gcc.pdf, page 216 recommends to put the function definition in a header file with the keywords inline and extern.
If 'vTaskIncrementTick' is put as 'extern inline void vTaskIncrementTick( void )' in 'task.h' inlining will work with GCC, too. Of cause some declarations of variables, functions and macros of 'tasks.c' are addtionally necessary in 'task.h'.

I found the above mentioned document at http://www.gnuarm.org/. Its title is 'Using the GNU Compiler Collection' for GCC 3.3.2 and dated from 20. December 2002. A newer version doesn't seem to be available.

The compiler command which I used is
arm-elf-gcc -c -I../../Source/Demo -I../../Source/FreeRTOS_4.0.4/Source/include -I../../Source/FreeRTOS_4.0.4/Source/portable/GCC/ARM7_AT91SAM7S -I../../Source/Utilities -Wall -Wextra -Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations -Wno-strict-aliasing -Winline -D THUMB_INTERWORK -D SAM7_GCC -mthumb-interwork -mcpu=arm7tdmi -MMD -finline-limit=1000 -Os ../../Source/FreeRTOS_4.0.4/Source/portable/GCC/ARM7_AT91SAM7S/portISR.c -o portISR.o

Best regards


RE: FreeRTOS 4.0.4, GCC: Inlining

Posted by Nobody/Anonymous on July 19, 2006
The inline is a legacy thing. Most portmacro.h files include the lilne

#define inline

to remove it from the code and prevent any warnings.

RE: FreeRTOS 4.0.4, GCC: Inlining

Posted by Thomas K.-H. Nittel on July 19, 2006
of cause warnings can be avoided this way. But I want my code to be inlined so that the function call overhead is spared. For an example see my posting 'RE: FreeRTOS 4.0.4, AT91SAM7X256, Timertick
2006-07-19 14:05'

[ Back to the top ]    [ About FreeRTOS ]    [ Sitemap ]    [ ]

Copyright (C) Amazon Web Services, Inc. or its affiliates. All rights reserved.

Latest News

FreeRTOS kernel V10.0.1 is available for immediate download. Now MIT licensed.

FreeRTOS Partners

ARM Connected RTOS partner for all ARM microcontroller cores

IAR Partner

Microchip Premier RTOS Partner

RTOS partner of NXP for all NXP ARM microcontrollers

STMicro RTOS partner supporting ARM7, ARM Cortex-M3, ARM Cortex-M4 and ARM Cortex-M0

Texas Instruments MCU Developer Network RTOS partner for ARM and MSP430 microcontrollers

OpenRTOS and SafeRTOS