Strip debug symbols from binary packages

The _psycopg.so library goes down from 1.6mb to 300k in Linux packages.

Author: dvarrazzo

scripts/build/build_manylinux2014.sh

@@ -41,6 +41,7 @@ done
 
 # Bundle external shared libraries into the wheels
 for whl in "${prjdir}"/dist/*.whl; do
+    "${dir}/strip_wheel.sh" "$whl"
     auditwheel repair "$whl" -w "$distdir"
 done
 

scripts/build/build_manylinux_2_24.sh

@@ -41,6 +41,7 @@ done
 
 # Bundle external shared libraries into the wheels
 for whl in "${prjdir}"/dist/*.whl; do
+    "${dir}/strip_wheel.sh" "$whl"
     auditwheel repair "$whl" -w "$distdir"
 done
 

scripts/build/strip_wheel.sh

@@ -0,0 +1,41 @@
+#!/bin/bash
+
+# Strip symbols inplace from the libraries in a zip archive.
+#
+# Stripping symbols is beneficial (reduction of 30% of the final package, >
+# %90% of the installed libraries. However just running `auditwheel repair
+# --strip` breaks some of the libraries included from the system, which fail at
+# import with errors such as "ELF load command address/offset not properly
+# aligned".
+#
+# System libraries are already pretty stripped. _psycopg2.so goes around
+# 1.6M -> 300K (python 3.8, x86_64)
+#
+# This script is designed to run on a wheel archive before auditwheel.
+
+set -euo pipefail
+set -x
+
+wheel=$(realpath "$1")
+shift
+
+# python or python3?
+if which python > /dev/null; then
+    py=python
+else
+    py=python3
+fi
+
+tmpdir=$(mktemp -d)
+trap "rm -r ${tmpdir}" EXIT
+
+cd "${tmpdir}"
+$py -m zipfile -e "${wheel}" .
+
+find . -name *.so -ls -exec strip "$@" {} \;
+# Display the size after strip
+find . -name *.so -ls
+
+$py -m zipfile -c "${wheel}" *
+
+cd -