SIGSEGVをキャッチし、なおかつそこから元の処理を継続する。

segv.cpp

#include <iostream>
#include <signal.h>

typedef void (*sighandler_t)(int);

volatile sig_atomic_t a = 100;
volatile sig_atomic_t p;

void segvcatch(int sig) {
	signal(sig, SIG_IGN);
	//std::cout << "segv catched\t" << sig << std::endl;
	p = reinterpret_cast<sig_atomic_t>(&a);
	throw p;
	//std::cout << p << std::endl;
	signal(sig, segvcatch);
}

int main() {
	p = 0;
	
	if(SIG_ERR == signal(SIGSEGV, segvcatch)) {
		std::cout << "cannnot set segvcatch" << std::endl;
	}

	//std::cout << &a << std::endl;
	try {
		std::cout << *((int *)p) << std::endl;
	} catch (...) {
		std::cout << *((int *)p) << std::endl;
	}
	std::cout << "end of program" << std::endl;
}

segv2.cpp

#include <iostream>
#include <signal.h>

typedef void (*sighandler_t)(int);

volatile sig_atomic_t a = 100;
int * p;

void segvcatch(int sig) {
	signal(sig, SIG_IGN);
	std::cout << "segv catched\t" << sig << std::endl;
	throw p;
	//std::cout << p << std::endl;
	signal(sig, segvcatch);
}

int func() {
	std::cout << "func" << std::endl;
	std::cout << *p << std::endl;

	return 0;
}

int main() {
	p = 0;
	
	if(SIG_ERR == signal(SIGSEGV, segvcatch)) {
		std::cout << "cannnot set segvcatch" << std::endl;
	}

	//std::cout << &a << std::endl;
	try {
		func();
	} catch (...) {
		std::cout << "catch logic" << std::endl;
	}
	std::cout << "end of program" << std::endl;
}

$ g++ segv.cpp
$ ./a.exe
Segmentation fault (core dumped)

$ g++ segv.cpp -fnon-call-exceptions
100
end of program

$ g++ segv2.cpp
func
segv catched    11
catch logic
end of program

$ g++ segv2.cpp -fnon-call-exceptions
func
segv catched    11
catch logic
end of program

gcc 2.95.4 では -fnon-call-exceptions が未実装
gcc 3.4.4 では動く(Linux,Cygwinで確認)