Windows has limits on path length, approximately (as I don't remember exactly off-hand): 256 chars total in dir or file path 128 chars in each element in dir or file path
.duanec. From: make-w32-bounces+dcampbell=nvidia....@gnu.org [mailto:make-w32-bounces+dcampbell=nvidia....@gnu.org] On Behalf Of Erik Carstensen Sent: 2013-05-06 Monday 11:51 To: Eli Zaretskii Cc: make-w32@gnu.org Subject: Re: Any known problems with relative paths in VPATH on Windows? Here is a makefile that reproduces it. The makefile is a bit hacky (creates a directory and calls itself from it); this is just to be able to reproduce it in a single makefile. The 'else' clause is the relevant one. If you put the makefile in a reasonable path (I used c:\cygwin\tmp), it will find a, b and c, but not the long filename. SHELL=cmd.exe q=$(1)$(1)$(1)$(1)$(1) long=$(call q,01234567890123456789) ifeq ($(findstring $(long),$(shell cd)),) default: -mkdir $(long) $(MAKE) -C $(long) -f ..\Makefile else src=..\src\$(long) $(info $(shell mkdir ..\src) $(shell mkdir $(src))) files=a b c 0123456789012345678901234567890123456789 $(info $(foreach f,$(files),$(shell echo > $(src)/$(f)))) VPATH=$(src) default: $(files) @echo ok endif On Mon, May 6, 2013 at 6:22 PM, Eli Zaretskii <e...@gnu.org<mailto:e...@gnu.org>> wrote: > Date: Mon, 6 May 2013 15:45:43 +0200 > From: Erik Carstensen <mandolae...@gmail.com<mailto:mandolae...@gmail.com>> > > I found the problem, there seems to be a limit in VPATH resolution of > around 256 characters, where ..\ entries in the path are not collapsed. In > my example, I ran make from c:\path\very-long-build-dir, and had > ..\very-long-src-dir on VPATH; very-long-src-dir and very-long-build-dir > were a bit over 200 characters together, so some but not all files in the > src dir exceeded the length limit and were not found. > > I don't know where this limit comes from; if it's a Windows limitation, > there's not much we can do. In my example it would have helped to collapse > the ..\:s in VPATH before resolving files, but it would just move the > problem a few characters. I have solved it myself in my use case, by > printing a warning when detecting dangerously long paths. I'm not sure if > it would make sense for make itself to automatically warn on too long paths. I doubt that it has anything to do with Windows. I'll look into this, but it would help if you could show a simple example that can be used to reproduce this problem. Thanks.
_______________________________________________ Make-w32 mailing list Make-w32@gnu.org https://lists.gnu.org/mailman/listinfo/make-w32
