Float / Double issues

[Tim Hockin <thockin@cobaltnet.com>]

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Hey gang - I have what seems to be two seperate issues on Mips/Linux
(cobalt boxes).

1) Programs using doubles with pthreads get corrupted data in the
doubles.
2) Floats and va_arg crash with an FPE

below are two snippets that show these, at least on our boxes.  If
someone could confirm or deny their existence on any other platform?


Tim




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#include <stdio.h>
#include <pthread.h>
#include <stdarg.h>

void doit(int, double, unsigned int);
void vait(unsigned int, ...);
void *ptfn(void *);
void doit2(int, int);
void vait2(int, ...);
void *ptfn2(void *);

int main() 
{
	pthread_t pt1;
	double d1 = 1.234; 

	printf("Without threads: \n");
	ptfn((void *)&d1);
	printf("\n");
	fflush(stdout);

	printf("With threads: \n");
	pthread_create(&pt1, NULL, ptfn, &d1);
	printf("\n");
	fflush(stdout);

	pthread_exit(0);
	return 0;
}

void *ptfn(void *x)
{
	char ar[16];
	unsigned int decimals = 5;
	double d = *(double *)x;

	doit(1, d, decimals);
	vait(decimals, d);
}

void doit(int x, double d, unsigned int ui)
{
	char buff[331];

	sprintf(buff,"double: %.*f",ui,d);
	printf("%s\n", buff);
}

void vait(unsigned int ui, ...)
{
	double d=-10.0;
	va_list va;

	va_start(va, ui);

	printf("double before va_arg: %f\n", d);
	d = va_arg(va, double);
	printf("double after va_arg: %f\n", d);

	va_end(va);

	doit(1, d, ui);
}

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#include <stdio.h>
#include <stdarg.h>

void doit(int, float, unsigned int);
void vait(unsigned int, ...);
void *ptfn(void *);

int main() 
{
	float d1 = 1.234; 

	printf("Without threads: \n");
	ptfn((void *)&d1);
	printf("\n");
	fflush(stdout);

	return 0;
}

void *ptfn(void *x)
{
	char ar[16];
	unsigned int decimals = 5;
	float d = *(float *)x;

	doit(1, d, decimals);
	vait(decimals, d);
}

void doit(int x, float d, unsigned int ui)
{
	char buff[331];

	sprintf(buff,"float: %.*f",ui,d);
	printf("%s\n", buff);
}

void vait(unsigned int ui, ...)
{
	float d=-10.0;
	va_list va;

	va_start(va, ui);

	printf("float before va_arg: %f\n", d);
	d = va_arg(va, float);
	printf("float after va_arg: %f\n", d);

	va_end(va);

	doit(1, d, ui);
}