"Martin Crundall" <pgsql@ac6rm.net> writes:
> Not sure how to tell. I didn't explicitly specify anything like this
> during the ./configure step of install. Poking around in the souce
> directory, I pulled this out of config.cache ...
> configure:1243: checking whether the C compiler (gcc -O9 -funroll-loops
> -ffast-math -malign-double -mcpu=pentiumpro -march=pentiumpro ^^^^^^^^^^^
> -fomit-frame-pointer -fno-exceptions ) works
Bingo: something is supplying a whole bunch of "helpful" optimization
options, including -ffast-math which is what's causing your problem.
Left to its own devices, configure would have only selected "-O2" as
the default flags for gcc.
I suspect if you try "env | grep CFLAGS" you will find that the problem
is a CFLAGS environment variable that you're inheriting from somewhere.
If so, you could "unset CFLAGS" and then re-run configure, rebuild,
reinstall (you won't need to initdb fortunately, just reinstall the
executables).
If it's not coming from a CFLAGS environment variable setting then
you'll need to look harder.
regards, tom lane