#!/bin/bash

Fail()
{
    echo "ERROR($0): $1"
    exit 1
}

[[ -z "${CC}" ]] && CC=gcc
echo "$0: C compiler = ${CC}"

if [[ "$1" == "debug" ]]; then
    BUILDOPT='-g -Og'
elif [[ "$1" == "opt" ]]; then
    BUILDOPT="$2"
    echo "Using custom build options: ${BUILDOPT}"
elif [[ -z "$1" ]]; then
    # On Arch Linux running gcc 9.3.0 on aarch64 (Rasbperry Pi 3),
    # started to get some numeric discrepancies in 'ctest check' output
    # until I turned off "fp contract" optimizations.
    # Some processors (including 64-bit ARM) have the ability to evaluate floating point
    # expressions like "a*b + c" with a single instruction, and to
    # do so without rounding the intermediate multiplication result.
    # Although this is *more* accurate, it produces results that are
    # different from other processors, which is counterproductive for
    # unit tests. Therefore, I turn it off here. Users of the C
    # version of Astronomy Engine can safely build other code with '-O3' by itself.
    BUILDOPT='-O3 -ffp-contract=off'
else
    Fail "unrecognized command line option"
fi

${CC} ${BUILDOPT} -Wall -Werror -o ctest -I ../source/c/ ../source/c/astronomy.c ctest.c -lm || Fail "Error building ctest"

echo "$0: Built 'ctest' program."
exit 0