Invoking -v for clang during buildworld

[bob prohaska]

On Sat, Jan 16, 2021 at 11:17:52AM -0800, Mark Millard wrote:
> 
> 
> On 2021-Jan-16, at 07:55, bob prohaska <fbsd at www.zefox.net> wrote:
> 
> > On Fri, Jan 15, 2021 at 09:25:00PM -0800, Mark Millard wrote:
> >> 
> >> On 2021-Jan-15, at 20:37, bob prohaska <fbsd at www.zefox.net> wrote:
> >> 
> >>> While playing with -current on armv7 using a raspberry pi 2 v1.1 
> >>> an error crops up with recent kernels while building world:
> >>> 
> >>> ++: error: linker command failed with exit code 1 (use -v to see invocation)
> >>> *** [clang.full] Error code 1
> >>> 
> >>> make[5]: stopped in /usr/freebsd-src/usr.bin/clang/clang
> >>> 
> >>> How does one invoke -v in this situation?
> >> 
> >> Going a different direction: Going to publish the build log
> >> someplace? There is likely more there of interest to isolating
> >> the issue(s).
> >> 
> > I've put what I hope is a useful picture at
> > http://www.zefox.net/~fbsd/rpi2/buildworld/
> 
> Looks to me like your -DNO_CLEAN based build is reusing one or
> more files with inappropriate/incomplete contents that need to
> be regenerated: there are a number of undefined symbols stopping
> the linker during its attempt to build the "usr.bin/clang/clang
> (all)" material. See below.
> 
[examples snipped]
> 
> FYI:
> 
> I found this by noting the "all_subdir_usr.bin" below and
> searching backwards for prior examples and seeing what was
> after those examples.
> 
> --- all_subdir_usr.bin ---
> c++: error: linker command failed with exit code 1 (use -v to see invocation)
> *** [clang.full] Error code 1
> 
> 

It never dawned that I wasn't looking at the first error message.
 
> 
> The undefined symbols seem unlikely to be a voltage problem.
> 
> The zeros are from the units for the integers not being volts
> but micro volts. (Which is not the same as saying measurements
> reach that scale of accuracy.)
> 

So long as  they're measured values they might be worth keeping track of.
I thought maybe they were some sort of input or placeholder values.

> >> I use META_MODE builds. One thing they do is record the
> >> command used to try to produce each file. So in that kind
> >> of context, identifying what it was trying to build allows
> >> finding the related NAME.meta file and looking in it.
> >> 

Not needed now, but worth remembering for the future.

> 
> I see no specific evidence for a kernel problem being involved.
> 
Agreed. The problem is the operator.

Thanks for your patience!

bob prohaska