sed-4.1.5 build failure on NetBSD 3.0

[Bruno Haible]

Hi Paolo,

GNU sed-4.1.5 fails to build on NetBSD 3.0:
$ ./configure
$ make
...
if gcc -DHAVE_CONFIG_H -I. -I. -I..  -I../lib -I../intl -I..  -I../lib 
-I../intl  -I/home/bruno/gnu/include  -g -O2 -MT regex.o -MD -MP -MF 
".deps/regex.Tpo" -c -o regex.o regex.c;  then mv -f ".deps/regex.Tpo" 
".deps/regex.Po"; else rm -f ".deps/regex.Tpo"; exit 1; fi
In file included from regex.c:61:
regex_internal.h:413:20: alloca.h: No such file or directory
*** Error code 1

Stop.
make: stopped in /home/bruno/build/sed-4.1.5/lib
*** Error code 1

The problem is that you took regex from gnulib, ignoring its module
dependencies, and NetBSD 3's gcc has no <alloca.h>. After I copy the
lib/alloca_.h from gnulib and execute the corresponding Makefile rules,
the build completes fine and all tests pass.

Bruno