I have a very strange problem. It sounds to me that this is a known problem, but I cannot find any actual solutions for, or any solid explanations of it.
Here is my setup:
Host: Win7 PC, plenty of RAM.
Target: STM32F303RE Cortex M4 @ 64 MHz, on Nucleo32 board with Integrated ST-LINK 2.1
Toolchain: uVision V5.16
Preprocessor Symbols: USE_STDPERIPH_DRIVER,STM32F303xE,__CPLUSPLUS__FPU_PRESENT,__FPU_USED
Misc Controls: --C99 --cpp
All builds well. All optimization turned off.
The problem is during runtime. The processor ends up in a hardfault handler after a few C++ object instantiantions. Where exactly? I've marked this by splitting my code snippet. Now, I'm sort of new to C++ details and inner workings, but it sounds like I have the same problem as this bloke: Segmentation fault caused/avoided by changing source file order in Makefile
But also, not clear solution is explained. Perhaps it is not the C++ instantiation at fault. Though there is no solution found. Here is the gist of my program which demonstrates the problem: This first section of code "appears" to run well, until the section block I've separated out for your attention.
#include "main.h"
#include "stm32f30x.h"
#include "stdint.h"
#include "stdio.h"
#include "string.h"
#include "math.h"
#include "usart.h"
#include "can.h"
#include "utils.h"
#include "led.h"
#include "i2c.h"
#include "sabertooth.h"
#include "FuzzyRule.h"
#include "FuzzyComposition.h"
#include "Fuzzy.h"
#include "FuzzyRuleConsequent.h"
#include "FuzzyOutput.h"
#include "FuzzyInput.h"
#include "FuzzyIO.h"
#include "FuzzySet.h"
#include "FuzzyRuleAntecedent.h"
Fuzzy* fuzzy = new Fuzzy();
int main(void)
{
/*************************************
* Input 1
************************************/
// Two "crossing ramp" sets for rowWidth i.e. "tolerance" of the row
FuzzyInput* rowWidth = new FuzzyInput(1);
FuzzySet* lowTolerance = new FuzzySet(0.0f, 0.0f, 0.0f, 120.0f);
rowWidth->addFuzzySet(lowTolerance);
FuzzySet* highTolerance = new FuzzySet(0.0f, 120.0f, 120.0f, 120.0f);
rowWidth->addFuzzySet(highTolerance);
fuzzy->addFuzzyInput(rowWidth);
USART1_puts("row width added as fuzzy input..");
/*************************************
* Input 2
************************************/
// Five Sets for "difference between R and L distances"
FuzzyInput* distDiff = new FuzzyInput(2);
FuzzySet* tooFarRight = new FuzzySet(-60.0f, -60.0f, -54.0f, -30.0f);
distDiff->addFuzzySet(tooFarRight);
FuzzySet* right = new FuzzySet(-54.0f, -30.0f, -30.0f, 0.0f);
distDiff->addFuzzySet(right);
FuzzySet* centered = new FuzzySet(-30.0f, 0.0f, 0.0f, 30.0f);
distDiff->addFuzzySet(centered);
FuzzySet* left = new FuzzySet(0.0f, 30.0f, 30.0f, 54.0f);
distDiff->addFuzzySet(left);
FuzzySet* tooFarLeft = new FuzzySet(30.0f, 54.0f, 60.0f, 60.0f);
distDiff->addFuzzySet(tooFarLeft);
fuzzy->addFuzzyInput(distDiff);
USART1_puts("centering dist added as fuzzy input...");
/*************************************
* Output 1
************************************/
FuzzyOutput* motorSpeedDiff = new FuzzyOutput(1);
// Seven sets for steering modes to take (close ones narrow far ones wider)
FuzzySet* hardRight = new FuzzySet(-30.0f, -30.0f, -30.0f, -15.0f);
motorSpeedDiff->addFuzzySet(hardRight);
USART1_puts("\thardRight");
FuzzySet* lightRight = new FuzzySet(-15.0f, -5.0f, -5.0f, 0.0f);
motorSpeedDiff->addFuzzySet(lightRight);
USART1_puts("\tlightRight");
This is the last serial message I see in the terminal "lightRight" Hard fault occurs in next call to new FuzzySet()below this line.
FuzzySet* nomRight = new FuzzySet(-30.0f, -15.0f, -15.0f, -5.0f);
motorSpeedDiff->addFuzzySet(nomRight);
USART1_puts("\tnomRight");
FuzzySet* lightLeft = new FuzzySet(0.0f, 5.0f, 5.0f, 15.0f);
motorSpeedDiff->addFuzzySet(lightLeft);
USART1_puts("\tlightLeft");
FuzzySet* goStraight = new FuzzySet(-5.0f, 0.0f, 0.0f, 5.0f);
motorSpeedDiff->addFuzzySet(goStraight);
USART1_puts("\tgoStraight");
FuzzySet* nomLeft = new FuzzySet(5.0f, 15.0f, 15.0f, 30.0f);
motorSpeedDiff->addFuzzySet(nomLeft);
USART1_puts("\tnomLeft");
FuzzySet* hardLeft = new FuzzySet(15.0f, 30.0f, 30.0f, 30.0f);
motorSpeedDiff->addFuzzySet(hardLeft);
USART1_puts("\thardLeft");
fuzzy->addFuzzyOutput(motorSpeedDiff);
USART1_puts("motor steering added as fuzzy output");
lotsMoreSetupCode();
while(1)
{
USART1_puts("Done!");
stop(1); // Blink LED forever
}
}
So clearly, I am just making a bunch of these fuzzy sets, which are each a collection of 4 floats, but somewhere a le-wild pointer flies?
Here is the constructor found in FuzzySet.cpp: (Part of a fuzzy logic library I did not write) This SAME program runs well on an Arduino, but not this processor. Compiler difference?
FuzzySet::FuzzySet(){
}
FuzzySet::FuzzySet(float a, float b, float c, float d){
this->a = a;
this->b = b;
this->c = c;
this->d = d;
this->pertinence = 0.0;
}
It sounds like something to do with static variables being accessed by other staticly declared functions in other contexts.
But I have nothing declared static.
Someone in the stack exchange link says it might be a linker fault. Do you agree? How to repair this?
Any ideas on what is actually happening?
I've set up the nice hard fault handler which prints register info, but apparently the error occurs even before main(). So going to the assembly code when things get jumbled doesn't seem useful.
How to go about repairing this? Thanks for your C++ expertise!
