issues with doubles and -fno-schedule-insns2

[Matthew J Fletcher <mfletcher at serck-controls dot co dot uk>]

Hi

i have a C code snipit that causes problems with gcc 3.3.4 and 3.4.1, i have 
not tried the v4 snapshots, in all cases are am hosted and targeting on i386.

void test(void)
{	
	unsigned int Value[2] = { 0x7FF00000, 0x7FF00000 };
	double *ValueD = (double *)&Value[0];
	
	// (*ValueD) should be "nan"
}

i've did some elimination and got the following results, seems 
-fno-schedule-insns2 is breaking things.

// gcc-3.3.4 -O3 -fno-schedule-insns2 (works)
// gcc-3.3.4 -O3 (fail) '(*ValueD) = 2.15833'
// gcc-3.3.4 -O2 -fno-schedule-insns2 (works)
// gcc-3.3.4 -O2 (fail) '(*ValueD) = 2.15833'
// gcc-3.3.4 -O1 (works)
// gcc-3.3.4 -O0 (works)

// gcc-3.4.1 -O3 -fno-schedule-insns2 (works)
// gcc-3.4.1 -O3 (fail) '(*ValueD) = 2.122e-314'
// gcc-3.4.1 -O2 -fno-schedule-insns2 (works)
// gcc-3.4.1 -O2 (fail) '(*ValueD) = 2.122e-314'
// gcc-3.4.1 -O1 (works)
// gcc-3.4.1 -O0 (works)


a small modification to the code to,..

unsigned int Value[2] = { 0x7FF00000, 0x7FF00000 };

void test(void)
{	
	double *ValueD = (double *)&Value[0];
	
	// (*ValueD) should be "nan"
}

and all the above compiler combinations work.

am i doing something wrong ?

regards
---
Matthew J Fletcher
Embedded Software
Serck Controls Ltd
---
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