attribute requires static parameter? #1018
Description
The following (stupid) MWE crashes nvc:
file: stable.vhd
ENTITY stable IS
END ENTITY stable;
ARCHITECTURE arch OF stable IS
SIGNAL a, b : BOOLEAN;
BEGIN
a <= FALSE;
b <= a'STABLE(NOW - a'LAST_EVENT);
END ARCHITECTURE arch;Crash:
nvc -a stable.vhd -e stable
*** Caught signal 11 (SEGV_MAPERR) [address=0xffffffffffffff98, ip=0x55f739b2a1f5] ***
[0x55f739a43f0d] ../src/util.c:872 signal_handler
[0x7f891c66851f] (/usr/lib/x86_64-linux-gnu/libc.so.6)
[0x55f739b2a1f5] ../src/rt/model.c:1706 split_nexus.lto_priv.0
[0x55f739b47f8b] ../src/rt/model.c:4008 x_last_event
[0x55f739b47f8b] ../src/rt/model.c:356 __nvc_last_event
[0x55f739b4b065] ../src/jit/jit-exits.c:780 __nvc_do_exit
[0x55f739b4cfa6] ../src/jit/jit-interp.c:831 interp_loop
[0x55f739b4cfa6] ../src/jit/jit-interp.c:1101 jit_interp
[0x55f739b37a0b] ../src/jit/jit-core.c:666 jit_try_vcall.lto_priv.0
[0x55f739b38bdf] ../src/jit/jit-core.c:728 jit_try_call
[0x55f739aa6332] ../src/eval.c:424 eval_instance
[0x55f739aa6332] ../src/eval.c:1425 elab_lower.lto_priv.0
[0x55f739aa7ed1] ../src/elab.c:1536 elab_architecture.lto_priv.0
[0x55f739b84f74] ../src/elab.c:2313 elab.constprop.0
[0x55f739a4ad62] ../src/nvc.c:476 elaborate
[0x55f739a482ca] ../src/nvc.c:2115 process_command
[0x55f739a48785] ../src/nvc.c:1799 cover_report_cmd
[0x55f739a48785] ../src/nvc.c:2145 process_command
[0x55f739a40687] ../src/nvc.c:2257 main
nvc 1.14.0 (1.14.0.r0.g157b0f6) (Using LLVM 14.0.0) [x86_64-pc-linux-gnu]
This seems to be because I did something stupid and tried to use a non static parameter for the attribute. At least this seems to be the case as GHDL and QuestaSim both complain about it:
GHDL:
ghdl -a stable.vhd
stable.vhd:8:23:error: parameter of signal attribute must be static
QuestaSim:
vcom stable.vhd
** Error: stable.vhd(8): Attribute "STABLE" requires a globally static parameter.
Note that ghdl and questa both fail and emit an error during analyze phase. Nvc does not complain at all. Only if the design is elaborated then nvc crashes.
Cheers!