compiler errors

##Template-related errors

Not loading template implementations

Errors look like:

// gcc
'XXX' undeclared (first use in this function)
expected expression before ‘YYY’

There are a lot of standard template implementations commonly used in ATS2, and they are not loaded by default (for instance, in kernel or embedded programming, it is best not to load what one doesn't need). This can usually be fixed by adding this at the start of your file:

#include "share/atspre_staload.hats"

By default, the ATS compiler only staloads everything in prelude except its template implementations, which is a very common point of confusion for ATS newcomers.

Template functions on non-abstract types

Using a function template on a non-abstract type can result in this (the rules for templates are not all written down and the implementation is not finished):

falcon_cnfize_dats.c: In function âATSLIB_056_prelude__list_vt_freelin__clear__7__1â:
falcon_cnfize_dats.c:1698:1: error: âPMVtmpltcstmatâ undeclared (first use in this function)
falcon_cnfize_dats.c:1698:1: note: each undeclared identifier is reported only once for each function     it appears in
falcon_cnfize_dats.c:1698:1: error: âgclear_refâ undeclared (first use in this function)
falcon_cnfize_dats.c:1698:1: warning: implicit declaration of function âS2EVarâ [-Wimplicit-function-declaration]
falcon_cnfize_dats.c:1698:1: error: expected expression before â)â token
exec(gcc -std=c99 -D_XOPEN_SOURCE -I/home/brandon/ATS-Postiats -I/home/brandon/ATS-Postiats/ccomp/runtime -I/home/brandon/ATS-Postiats/contrib -DATS_MEMALLOC_LIBC -D_GNU_SOURCE -c falcon_cnfize_dats.c) = 256

To avoid this, either don't use a template (for now), or try to use an abstract type:

abstype mytype = ptr

Then you introduce cast functions where needed to convert between the abstract type and other (view)types.

Missing Linker Flag Errors

Didn't specify which memory allocation functions to use

Usually you'll want to properly pass -DATS_MEMALLOC_LIBC to patscc. The main thing you'll see here is undefined reference to atsruntime_malloc_undef'` (usually several times).

/tmp/cchxHdy9.o: In function atspre_arrayptr_free':
gurobi_mip1_dats.c:(.text+0x1d4): undefined reference toatsruntime_mfree_undef'
/tmp/cchxHdy9.o: In function  _057_media_057_RAID5_057_home_057_brandon_057_ATS_055_Postiats_057_contrib_057_libats_055_bbarker_057_ats    optml_057_TEST_057_gurobi_mip1_056_dats__mytest_main':
gurobi_mip1_dats.c:(.text+0x4dc): undefined reference toatsruntime_malloc_undef'
gurobi_mip1_dats.c:(.text+0x54e): undefined reference to `atsruntime_malloc_undef'
collect2: ld returned 1 exit status

Alternatively, for more customization, see Stack and heap allocation.