Package OpenBLAS and use OpenBLAS in scipy

.github/workflows/main.yml

@@ -128,13 +128,22 @@ jobs:
           make -C cpython
           ccache -s
 
+      - name: build openblas
+        shell: bash -l {0}
+        run: |
+          # This is necessary to use the ccache from emsdk
+          source pyodide_env.sh
+          ccache -z
+          PYODIDE_PACKAGES="openblas" make
+          ccache -s
+
       - name: build Pyodide core + numpy
         shell: bash -l {0}
         run: |
           # This is necessary to use the ccache from emsdk
           source pyodide_env.sh
           ccache -z
-          PYODIDE_PACKAGES="core,numpy" make
+          PYODIDE_PACKAGES="core,numpy,openblas" make
           ccache -s
 
       - name: check-size

packages/openblas/meta.yaml

@@ -0,0 +1,24 @@
+package:
+  name: openblas
+  version: de4d5646eb1ac6a0e663a4c9bc797dad8226aedb
+
+source:
+  sha256: 148a959b61ffa4d77e810ceb3114765501d70c982cbb302a00954b81bc918e46
+  url: https://github.com/xianyi/OpenBLAS/archive/de4d5646eb1ac6a0e663a4c9bc797dad8226aedb.zip
+  patches:
+    - patches/0001-Add-Wno-implicit-function-declaration-flag.patch
+
+build:
+  type: shared_library
+  script: |
+    # seems like .zip does not maintain executable flags, need to reset these
+    chmod u+x c_check
+    chmod u+x f_check
+    chmod u+x exports/gensymbol
+    make CC=emcc HOSTCC=gcc TARGET=RISCV64_GENERIC NOFORTRAN=1 USE_THREAD=0
+    mkdir -p dist
+    cp libopenblas.so dist/
+    mkdir -p ${WASM_LIBRARY_DIR}/{lib,include}
+    # TODO do I need include as in CLAPACK?
+    # cp -r INCLUDE/* ${WASM_LIBRARY_DIR}/include
+    cp dist/libopenblas.so ${WASM_LIBRARY_DIR}/lib

packages/openblas/patches/0001-Add-Wno-implicit-function-declaration-flag.patch

@@ -0,0 +1,25 @@
+From 09fd1aa0aa6a98e1cebaa6e34fca1e424dab8f48 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Lo=C3=AFc=20Est=C3=A8ve?= <loic.esteve@ymail.com>
+Date: Fri, 9 Dec 2022 16:40:13 +0100
+Subject: [PATCH] Add -Wno-implicit-function-declaration flag
+
+---
+ Makefile.rule | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/Makefile.rule b/Makefile.rule
+index 5f787a9c..6890046a 100644
+--- a/Makefile.rule
++++ b/Makefile.rule
+@@ -228,7 +228,7 @@ NO_AFFINITY = 1
+ # Common Optimization Flag;
+ # The default -O2 is enough.
+ # Flags for POWER8 are defined in Makefile.power. Don't modify COMMON_OPT
+-# COMMON_OPT = -O2
++COMMON_OPT = -O2 -Wno-implicit-function-declaration
+
+ # gfortran option for LAPACK to improve thread-safety
+ # It is enabled by default in Makefile.system for gfortran
+-- 
+2.34.1
+