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Re: Anyone else sees a bootstrap failure (Linux-x86)?


Ranjit Mathew writes:
 > Andrew Haley wrote:
 > 
 > >  > "-pipe" is useful and eliminates a lot of temporary files creation,
 > >  > somewhat speeding up the build.
 > > 
 > > Not on any sane platform.  Really, have you ever seen a significant
 > > speedup?  Or is file creation so horribly slow on Windows that this is
 > > a real issue?
 > 
 > >From the GCC manual:
 > 
 > ----------------------------- 8< -----------------------------
 > -pipe
 >     Use pipes rather than temporary files for communication 
 > between the various stages of compilation. This fails to 
 > work on some systems where the assembler is unable to read from 
 > a pipe; but the GNU assembler has no trouble.
 > ----------------------------- 8< -----------------------------
 > 
 > It *looks like* "-pipe" should be at least as fast, if not
 > faster, than using temporary files. However, I have never
 > really properly compared the two alternatives.

If -pipe was such a good idea it would be the default.  It isn't.

 > This choice was based more on a gut feeling and a large amount of
 > anecdotal evidence (mainly, Slashdot comments - the ones on the
 > *old* Slashdot, not the weirdness that currently carries the same
 > name).
 > 
 > By "sane", do you mean a system that does a healthy amount of
 > file-system caching to avoid unnecessary writes to the disk, making
 > using temporary files almost as fast as pipes?

Faster.  No interlocks, you see.  

Write the whole file, then read it.  That's much less work than all
the management of pipes.

 > BTW, I build only on x86-Linux now.

Then -pipe is slowing you down.

Andrew.


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