To continue from/with

Procedure and build scripts for Unbundled Builds (Slowroll)
https://lists.cinelerra-gg.org/archives/list/cin@lists.cinelerra-gg.org/thread/DDID2KFLR2DV4AML4XHVLJDTQVHVSKFZ/

Edited bld.sh ./configure line:

cat bld.sh

#!/bin/bash
#  IMPORTANT comments below to change the configure line
# For newer operating system versions, add --enable-libsvtav1
# For really old versions, such as ubuntu 16, add --enable-libaom=no
# Faster compile if include --disable-x265_hidepth
# To add OpenCV plugins, add --with-opencv=sta,tar=https://download.cinelerra-gg.org/download.php?file=opencv%2Fopencv-20200306.tgz
( ./autogen.sh
#  ./configure --with-single-user --with-booby
./configure --with-single-user --disable-static-build --without-thirdparty --without-libdpx --enable-ffmpeg
  make && make install ) 2>&1 | tee log
mv Makefile Makefile.cfg
cp Makefile.devel Makefile
--------------

Test-run

./bld.sh
.........
checking for openexr available... yes
configure: error: lv2 requested but no lv2 headers found
make: *** No targets specified and no makefile found.  Stop.
mv: cannot stat 'Makefile': No such file or directory

------

The start of blds/bld_prepare.sh say

#!/bin/bash
#  need lv2 plugins (eg. lv2-calf-plugin)

lv2-dev is included in only two package lists, for Ubuntu and Debian!?

I add-installed lv2-devel, next also liblilv-0-devel and lv2-calf on Slowroll,
but still bld.sh claims 
"configure: error: lv2 requested but no lv2 headers found"

So I'm stuck here (again).

----

Try to verify if lv2.h are installed:

find /usr/include -name lv2.h
/usr/include/lv2.h
/usr/include/lv2/lv2.h
/usr/include/lv2/core/lv2.h
/usr/include/lv2/lv2plug.in/ns/lv2core/lv2.h

pkg-config --cflags lv2

pkg-config --cflags lv2.h
Package lv2.h was not found in the pkg-config search path.
Perhaps you should add the directory containing `lv2.h.pc'
to the PKG_CONFIG_PATH environment variable
Package 'lv2.h' not found