Need to install liblz4-dev

On Wed, Mar 04, 2026 at 12:50:24AM -0500, Bruce Momjian wrote:

However, I had /usr/lib/x86_64-linux-gnu/liblz4.so.1 installed on Debian
13. I had to install liblz4-dev ("dev") to allow the configure/compile
to succeed.

That's because of 7c1849311e49, hence my fault. You can also bypass
the failure by appending a --without-lz4 to your configure switches,
like one can do for ICU.
--
Michael

On Wed, 4 Mar 2026 at 07:15, Michael Paquier <michael@paquier.xyz> wrote:

On Wed, Mar 04, 2026 at 12:50:24AM -0500, Bruce Momjian wrote:

However, I had /usr/lib/x86_64-linux-gnu/liblz4.so.1 installed on Debian
13. I had to install liblz4-dev ("dev") to allow the configure/compile
to succeed.

That's because of 7c1849311e49, hence my fault.

"Fault" seems the wrong word. This error is intentional. So you have to
go out of your way to build postgres in a way that cannot open
datadirs created by the default configuration.

On Wed, Mar 4, 2026 at 08:17:57AM +0100, Jelte Fennema-Nio wrote:

On Wed, 4 Mar 2026 at 07:15, Michael Paquier <michael@paquier.xyz> wrote:

On Wed, Mar 04, 2026 at 12:50:24AM -0500, Bruce Momjian wrote:

However, I had /usr/lib/x86_64-linux-gnu/liblz4.so.1 installed on Debian
13. I had to install liblz4-dev ("dev") to allow the configure/compile
to succeed.

That's because of 7c1849311e49, hence my fault.

"Fault" seems the wrong word. This error is intentional. So you have to
go out of your way to build postgres in a way that cannot open
datadirs created by the default configuration.

My bigger point is that I didn't see any notification on hackers that
installing liblz4-dev would be necessary to continue compiling master.
I thought other hackers would want to know this.

--
Bruce Momjian <bruce@momjian.us> https://momjian.us
EDB https://enterprisedb.com

Do not let urgent matters crowd out time for investment in the future.

On Wed, Mar 4, 2026 at 12:50 PM Bruce Momjian <bruce@momjian.us> wrote:

FYI, a few hours ago I started getting build errors on master due to
a missing liblz4 library error:

--> checking for liblz4... no
--> configure: error: Package requirements (liblz4) were not met:

--> Package 'liblz4', required by 'virtual:world', not found

Consider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.

Alternatively, you may set the environment variables LZ4_CFLAGS
and LZ4_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.
make: *** [../../../src/Makefile.global:870: ../../../config.status] Error 1

Works on my machine:

# to start
Program lz4 found: NO
Run-time dependency liblz4 found: NO (tried pkgconfig and cmake)
Run-time dependency lz4 found: NO (tried cmake)

john=# show default_toast_compression ;
default_toast_compression
---------------------------
pglz
(1 row)

# install just lz4 -- the build still succeeds
sudo dnf install lz4

<clean build dir>

Program lz4 found: YES (/usr/bin/lz4)
Run-time dependency liblz4 found: NO (tried pkgconfig and cmake)
Run-time dependency lz4 found: NO (tried cmake)

john=# show default_toast_compression ;
default_toast_compression
---------------------------
pglz
(1 row)

# also install liblz4-dev
Program lz4 found: YES (/usr/bin/lz4)
Run-time dependency liblz4 found: YES 1.10.0

john=# show default_toast_compression ;
default_toast_compression
---------------------------
lz4
(1 row)

--
John Naylor
Amazon Web Services