add ldl and lz

to remedy "ERROR: openssl not found"
bytedeco/javacpp-presets#32 (comment)

.github/workflows/build.yml

@@ -26,13 +26,14 @@ jobs:
         run: |
           brew install nasm yasm pkg-config cmake
 
-      - name: Setup tmate session
-        uses: mxschmitt/action-tmate@v3
+# Useful for debugging:
+#      - name: Setup tmate session
+#        uses: mxschmitt/action-tmate@v3
 
       - name: Build ffmpeg
         run: |
           while sleep 300; do echo "=====[ $SECONDS seconds still running ]====="; done &
-          SKIPINSTALL=yes VERBOSE=yes ./build-ffmpeg --build
+          ./build-ffmpeg --build
           kill %1
 
       - name: Check shared library

README.md

@@ -45,6 +45,8 @@ Wait for [Github Actions](https://github.com/mifi/ffmpeg-build-script/actions) a
 /usr/lib/libobjc.A.dylib (compatibility version 1.0.0, current version 228.0.0)
 ```
 
+There should definitely not be any non-standard libraries added, especially no `/usr/local/*`.
+
 Now download and test the artifacts.
 
 To make a new release, tag a new version, and then push the tags, for example:

build-ffmpeg

@@ -15,8 +15,8 @@ WORKSPACE="$CWD/workspace"
 CFLAGS="-I$WORKSPACE/include -mmacosx-version-min=${MACOS_MIN}"
 LDFLAGS="-L$WORKSPACE/lib -mmacosx-version-min=${MACOS_MIN}"
 LDEXEFLAGS=""
-# EXTRALIBS="-ldl -lpthread -lm -lz"
-EXTRALIBS="-lpthread -lm"
+# -ldl and/or -lz seems to be needed by openssl on x64 mac
+EXTRALIBS="-ldl -lpthread -lm -lz"
 MACOS_M1=false
 CONFIGURE_OPTIONS=()
 LATEST=false