[libcxx-dev] "Unknown warning" error when trying to compile libcxx tests for remote, bare-metal target

Dominik Montada via libcxx-dev libcxx-dev at lists.llvm.org
Mon May 18 05:31:14 PDT 2020

Hi there,

I'm trying to set up the libcxx tests to run on a remote, bare-metal 
target and am running into some issues with an unknown warning error:

error: unknown warning option '-Wno-aligned-allocation-unavailable'; did 
you mean '-Wno-debug-compression-unavailable'? 

It seems this flag should only get added to the compile options if it is 
supported through line 673 in config.py:


So I'm wondering why I still get the error message then, if it is 
apparently supported?

I have created <Target>RemoteTI in target_info.py and call llvm-lit with 
the following command line parameters from the libcxx root folder:

-sv --param target_triple=<triple> --param compile_flags="<some 
additional flags>" ./test

My custom target info is also defining some target specific compile flags.

Some very shallow, initial digging around leads me to suspect the 
-nostdinc flag that I'm setting in my target info. I need this flag 
since our internal backend does not set any default include paths yet 
and without it, clang tries to include my host system headers, which 
then leads to an include error. However I am unsure if the preprocessor 
triggers this error before clang checks for unknown warning options, 
therefore hiding the actual problem.

While I could circumvent the error by setting --param 
enable_warnings=false I would prefer to not use this workaround and 
instead fix the actual problem.

Is there something that I'm missing here or is this a bug in the 
regression test suite?



Dominik Montada                   Email: dominik.montada at hightec-rt.com
HighTec EDV-Systeme GmbH          Phone: +49 681 92613 19
Europaallee 19                    Fax:   +49-681-92613-26
D-66113 Saarbr├╝cken               WWW: http://www.hightec-rt.com

Managing Director: Vera Strothmann
Register Court: Saarbr├╝cken, HRB 10445, VAT ID: DE 138344222

This e-mail may contain confidential and/or privileged information. If
you are not the intended recipient please notify the sender immediately
and destroy this e-mail. Any unauthorised copying, disclosure or
distribution of the material in this e-mail is strictly forbidden.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/x-pkcs7-signature
Size: 5409 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/libcxx-dev/attachments/20200518/595e9ae8/attachment.bin>

More information about the libcxx-dev mailing list