ninja link failure

[Erik Smith]

This not really a GN question but I thought someone might have an idea.  Ninja reports FAILED on a link command but with no error.  When I run the same g++ link command directly, it works.  The line is about 250K characters in size, which is under ARG_MAX.  I have to imagine that chromium link commands can get at least as large. 

erik

[Erik Smith]

Update: my link line is too long and exceeds MAX_ARG_STRLEN on linux, which 131072 on my system.  I dug through the ninja source to discover it passes your command inline to /bin/sh with the -c option.  I replicated this outside of ninja and sh reports the error " Argument list too long".  For some reason, ninja doesn't show this output from sh.   I also found a thread in the ninja project with more details.  I suspect chromium has an approach that avoids this problem.

[K. Moon]

A lot of build tools take what's called a "response file" instead of passing everything on the command line, precisely for this reason. Ninja has support for this, and GN will use it under the right circumstances (https://gn.googlesource.com/gn/+/main/docs/reference.md#var_response_file_contents).

[Erik Smith]

The link for response_file for something similar in actions, but the rspfile and rspfile_contents in the link tool were trivial to implement.  Thanks!