Print more information on non fatal warnings

[antonblanchard]

Make non fatal warnings print the same one line of context
that fatal ones do, eg:

../../src/ieee2008/numeric_std-body.vhdl:3036:7:@1102465ns:(assertion warning): NUMERIC_STD.TO_INTEGER: metavalue detected, returning 0
in process .core_tb(behave).soc0@soc(behaviour).processor@core(behave).icache_0@icache(rtl).itlb_update

[antonblanchard]

I basically copied what the fatal error path does, I guess it should go into a common function.

[tgingold]

Isn't similar to the existing --backtrace-severity=LEVEL option ? Maybe it should be more advertized!

[antonblanchard]

I did stumble over that option, but it gives me no output. I wonder if the backtracing isn't working:

# ./core_tb --backtrace-severity=warning | head -30
...
../../src/ieee2008/numeric_std-body.vhdl:3036:7:@0ms:(assertion warning): NUMERIC_STD.TO_INTEGER: metavalue detected, returning 0
../../src/ieee2008/numeric_std-body.vhdl:3036:7:@0ms:(assertion warning): NUMERIC_STD.TO_INTEGER: metavalue detected, returning 0
../../src/ieee2008/numeric_std-body.vhdl:3036:7:@0ms:(assertion warning): NUMERIC_STD.TO_INTEGER: metavalue detected, returning 0

but the assert path gives me a line of useful info:

./core_tb --assert-level=warning |head -20
...
../../src/ieee2008/numeric_std-body.vhdl:3036:7:@0ms:(assertion warning): NUMERIC_STD.TO_INTEGER: metavalue detected, returning 0
./core_tb:error: assertion failed
in process .core_tb(behave).soc0@soc(behaviour).processor@core(behave).icache_0@icache(rtl).itlb_lookup

I've tried the Fedora 33 version of ghdl as well as the ghdl/ghdl:buster-llvm-7 ghdl image. I also tried building my own with libbacktrace.a.

[eine]

@antonblanchard would you mind providing a minimal reproducer that illustrates the feature? Then, I'll test it on multiple distros (Debian, Ubuntu and Fedora).

[antonblanchard]

@eine this shows the issue I'm hitting: backtrace-test.tar.gz

I try to use backtrace-severity=warning, but get no backtrace (I presume it's meant to):

ghdl -c --std=08 test_tb.vhdl test.vhdl -e test_tb
./test_tb --backtrace-severity=warning
../../src/ieee2008/numeric_std-body.vhdl:2025:7:@109345ns:(assertion warning): NUMERIC_STD."/=": metavalue detected, returning TRUE
../../src/ieee2008/numeric_std-body.vhdl:2025:7:@109355ns:(assertion warning): NUMERIC_STD."/=": metavalue detected, returning TRUE
...

My patch in this bug gives us one line of context, enough in this case to sort out what is going on:

../../src/ieee2008/numeric_std-body.vhdl:2025:7:@106715ns:(assertion warning): NUMERIC_STD."/=": metavalue detected, returning TRUE
in process .test_tb(behave).check_process

[eine]

@antonblanchard, I bet you did all your tests with LLVM backend. Running the tests with the three backends (Debian and Fedora) shows that --backtrace-severity=warning produces a different output for mcode, or for LLVM/GCC. See: https://github.com/eine/ghdl/runs/1678810852?check_suite_focus=true.

According to configure, --with-backtrace-lib needs to be used for LLVM, which we don't do when building the containers, and I don't think it's done in Fedora packages (/cc @sharkcz). However, for GCC it should be used automatically. Furthermore, if you built it explicitly...

[tmeissner]

According to configure, --with-backtrace-lib needs to be used for LLVM, which we don't do when building the containers, and I don't think it's done in Fedora packages (/cc @sharkcz). However, for GCC it should be used automatically. Furthermore, if you built it explicitly...

Are there any comprehensible reasons to not use ˋ--with-backtraceˋ in container builds? Would be useful also ther, I think.

[eine]

Are there any comprehensible reasons to not use ˋ--with-backtraceˋ in container builds? Would be useful also ther, I think.

Honestly, until today I was not aware that we were missing that feature. I knew libbacktrace was not used, but I thought it was only useful for debugging crashes. So, I agree, it'd be nice to add it. We need to find the package name and the location in each container, though.