Compile a Fortran-free WASM SciPy, with BLIS and semicolon-lapack

environment.yml

@@ -9,6 +9,8 @@ dependencies:
   - swig
   - make
   - cmake<4
+  - meson
+  - ninja
   - texinfo
   - autoconf
   - automake

packages/libblis/meta.yaml

@@ -15,6 +15,7 @@ source:
     # functions in the BLIS f2c compat layer. The patch is needed for SciPy's test
     # suite to pass.
     - patches/0002-CBLAS-interface-for-crotg-zrotg-zdrot-and-csrot.patch
+    - patches/0003-WASM-ABI-void-returns-lsame-xerbla_array.patch
 
 build:
   type: shared_library

packages/libblis/patches/0001-Compile-BLIS-to-WebAssembly.patch

@@ -1,7 +1,7 @@
 From 85aa27abe96e988adc8fdfbf61844bfd3307ccbf Mon Sep 17 00:00:00 2001
 From: Agriya Khetarpal <74401230+agriyakhetarpal@users.noreply.github.com>
 Date: Tue, 30 Jun 2026 06:06:59 +0530
-Subject: Compile BLIS to WebAssembly
+Subject: [PATCH 1/3] Compile BLIS to WebAssembly
 
 This is a squashed patch from https://github.com/agriyakhetarpal/blis/pull/1
 and applied on top of the v2.1 release of BLIS. See the release notes at:

packages/libblis/patches/0002-CBLAS-interface-for-crotg-zrotg-zdrot-and-csrot.patch

@@ -1,7 +1,7 @@
 From 8ef1abca0c395dbc02dba134c088fc403fe8c782 Mon Sep 17 00:00:00 2001
 From: Edward Smyth <117460141+edwsmyth@users.noreply.github.com>
 Date: Sun, 28 Jun 2026 20:47:26 +0100
-Subject: [PATCH 2/2] CBLAS interface for crotg, zrotg, zdrot and csrot (#926)
+Subject: [PATCH 2/3] CBLAS interface for crotg, zrotg, zdrot and csrot (#926)
 
 Details:
 - Add CBLAS wrappers for missing complex rot APIs, as requested in

packages/libsemilapack/meta.yaml

@@ -0,0 +1,44 @@
+package:
+  name: libsemilapack
+  version: "0.01.3-pre"
+  tag:
+    - library
+    - shared_library
+source:
+  url: https://github.com/ilayn/semicolon-lapack/archive/refs/tags/v0.01.3-pre.tar.gz
+  sha256: 5292396b9c2bffc1bf22dccad7acbf9f4fcb1edc0c45ed0f055d80f55e2a23a3
+
+build:
+  type: shared_library
+  script: |
+    export PKG_CONFIG_PATH="${WASM_LIBRARY_DIR}/lib/pkgconfig:${WASM_LIBRARY_DIR}/share/pkgconfig:${PKG_CONFIG_PATH}"
+
+    CC=emcc CXX=em++ AR=emar \
+    meson setup builddir --cross-file "${MESON_CROSS_FILE}" \
+      -Dblas=blis \
+      -Dfabi_shim=true \
+      -Dtests=false \
+      --default-library=static \
+      --prefix="${WASM_LIBRARY_DIR}"
+    ninja -C builddir
+    ninja -C builddir install
+
+    mkdir -p dist
+    emcc ${WASM_LIBRARY_DIR}/lib/libsemilapack.a \
+        ${WASM_LIBRARY_DIR}/lib/libsemilapack_fortran.a \
+        ${WASM_LIBRARY_DIR}/lib/libblis.so \
+        ${SIDE_MODULE_LDFLAGS} \
+        -o dist/libsemilapack.so
+
+    cp dist/libsemilapack.so ${WASM_LIBRARY_DIR}/lib/libsemilapack.so
+requirements:
+  host:
+    - libblis
+  # TODO: explore whether libblis is needed at runtime, or if the CBLAS symbols
+  # can be resolved at build time and the libblis.so dependency dropped
+  run:
+    - libblis
+about:
+  home: https://github.com/ilayn/semicolon-lapack
+  license: BSD-3-Clause
+  summary: LAPACK linear algebra routines implemented in C

packages/scipy/meta.yaml

@@ -20,13 +20,16 @@ package:
 source:
   url: https://files.pythonhosted.org/packages/source/s/scipy/scipy-1.18.0.tar.gz
   sha256: 67b2ad2ad54c72ca6d04975a9b2df8c3638c34ddd5b28738e94fc2b57929d378
-
   patches:
-    - patches/0001-gemm_-no-const.patch
-    - patches/0002-make-int-return-values.patch
-    - patches/0003-Fix-gees-calls.patch
-    - patches/0004-Remove-chla_transtype.patch
-    - patches/0005-Set-wrapper-return-type-to-int.patch
+    # TODO: figure out what to do with this patch. I realised that this patch is
+    # needed because the gees f2py wrapper is generated with the wrong signature.
+    # This comes up a lot in Schur. It passes two hidden Fortran string lengths
+    # for its char args (jobvs, sort) in the callstatement/callprotoargument.
+    # BLIS and semicolon-lapack (and the f2ced stack we had before, even) take no
+    # hidden lengths.
+    - patches/0001-Fix-gees-calls.patch
+    # Drop this patch with SciPy v1.19
+    - patches/0002-Fix-signatures-for-getrf-getri-and-trlib-dlagtm.patch
 build:
   vendor-sharedlib: true
   # NumPy 2.1 disabled visibility for symbols outside of extension modules
@@ -55,67 +58,16 @@ build:
   unvendor-tests: true
   # install-args=--tags=runtime,python-runtime,devel
   # Disable when running tests, enable when a PR is ready, i.e., building for distribution.
+  # TODO before merging: update to SciPy 2.0 when it arrives and drop -D_without-fortran=true
   backend-flags: |
     build-dir=build
-
-  # IMPORTANT: Other locations important in scipy build process:
-  # There are two files built in the "capture" pass that need patching:
-  #    _blas_subroutines.h, and _cython
-  # Scipy has a bunch of custom logic implemented in
-  # pyodide-build/pyodide_build/_f2c_fixes.py.
+    setup-args=-D_without-fortran=true
+    setup-args=-Dblas=blis
+    setup-args=-Dlapack=semicolon-lapack
   script: |
     set -x
-    git clone https://github.com/hoodmane/f2c.git --depth 1
-    (cd f2c/src && cp makefile.u makefile && sed -i "s/gram.c:/gram.c1:/" makefile && make)
-    export F2C_PATH=$(pwd)/f2c/src/f2c
-
-    echo F2C_PATH: $F2C_PATH
-    export NPY_BLAS_LIBS="-I$WASM_LIBRARY_DIR/include $WASM_LIBRARY_DIR/lib/libopenblas.so"
-    export NPY_LAPACK_LIBS="-I$WASM_LIBRARY_DIR/include $WASM_LIBRARY_DIR/lib/libopenblas.so"
-
-    sed -i 's/void DQA/int DQA/g' scipy/integrate/__quadpack.h
-
-    # Change many functions that return void into functions that return int
-    find scipy -name "*.c*" -type f | xargs sed -i 's/extern void F_FUNC/extern int F_FUNC/g'
-
-    sed -i 's/void F_FUNC/int F_FUNC/g' scipy/odr/__odrpack.c
-    sed -i 's/^void/int/g' scipy/odr/odrpack.h
-    sed -i 's/^void/int/g' scipy/odr/__odrpack.c
-
-    # sed -i 's/void F_FUNC/int F_FUNC/g' scipy/linalg/_lapack_subroutines.h
-    sed -i 's/void/int/g' scipy/linalg/cython_blas_signatures.txt
-    sed -i 's/void/int/g' scipy/linalg/cython_lapack_signatures.txt
-    sed -i 's/void BLAS_FUNC/int BLAS_FUNC/g' scipy/linalg/src/_common_array_utils.h
-    sed -i 's/^void BLAS_FUNC/int BLAS_FUNC/g' scipy/linalg/src/_common_array_utils.hh
-
-    # Change fortran functions called in C code to return int instead of void
-    # This adhoc regex checks function names ending with _ such as `void zgetrs_(`
-    sed -i 's/void BLAS_FUNC/int BLAS_FUNC/g' scipy/sparse/linalg/_propack/PROPACK/src/include/blaslapack_declarations.h
-    sed -i 's/void ARNAUD_BLAS/int ARNAUD_BLAS/g' scipy/sparse/linalg/_eigen/arpack/arnaud/src/blaslapack_declarations.h
-    sed -i 's/void BLAS_FUNC/int BLAS_FUNC/g' scipy/integrate/src/blaslapack_declarations.h
-    sed -i 's/void[[:space:]]*BLAS_FUNC/int BLAS_FUNC/g' scipy/optimize/src/blaslapack_declarations.h
-
-    sed -i 's/^void/int/g' scipy/interpolate/src/_fitpackmodule.c
-    sed -i 's/void BLAS_FUNC/int BLAS_FUNC/g' scipy/interpolate/src/__fitpack.h
-
-    sed -i 's/extern void/extern int/g' scipy/sparse/linalg/_dsolve/SuperLU/SRC/*.{c,h}
-    sed -i 's/PUBLIC void/PUBLIC int/g' scipy/sparse/linalg/_dsolve/SuperLU/SRC/*.{c,h}
-    sed -i 's/^void/int/g' scipy/sparse/linalg/_dsolve/SuperLU/SRC/*.{c,h}
-    sed -i 's/^void/int/g' scipy/sparse/linalg/_dsolve/*.{c,h}
-    sed -i 's/void \(.\)print/int \1/g' scipy/sparse/linalg/_dsolve/SuperLU/SRC/*.{c,h}
-    sed -i 's/TYPE_GENERIC_FUNC(\(.*\), void)/TYPE_GENERIC_FUNC(\1, int)/g' scipy/sparse/linalg/_dsolve/_superluobject.h
-
-    sed -i 's/^void/int/g' scipy/optimize/_trlib/trlib_private.h
-    sed -i 's/^void/int/g' scipy/_build_utils/src/wrap_dummy_g77_abi.c
-    sed -i 's/, int)/)/g' scipy/optimize/_trlib/trlib_private.h
-    sed -i 's/, 1)/)/g' scipy/optimize/_trlib/trlib_private.h
-
-    sed -i 's/^void/int/g' scipy/spatial/qhull_misc.h
-    sed -i 's/, size_t)/)/g' scipy/spatial/qhull_misc.h
-    sed -i 's/,1)/)/g' scipy/spatial/qhull_misc.h
 
-    # Input error causes "duplicate symbol" linker errors. Empty out the file.
-    echo "" > scipy/sparse/linalg/_dsolve/SuperLU/SRC/input_error.c
+    export PKG_CONFIG_PATH="${WASM_LIBRARY_DIR}/lib/pkgconfig:${WASM_LIBRARY_DIR}/share/pkgconfig:${PKG_CONFIG_PATH}"
 
     # https://github.com/mesonbuild/meson/blob/e542901af6e30865715d3c3c18f703910a096ec0/mesonbuild/backend/ninjabackend.py#L94
     # Prevent from using response file. The response file that meson generates is not compatible to pyodide-build
@@ -133,15 +85,11 @@ build:
 requirements:
   host:
     - numpy
-    - libopenblas
+    - libblis
+    - libsemilapack
     - libboost
   run:
     - numpy
-  executable:
-    - gfortran
-  constraint:
-    # Getting: Error: Dynamic linking error: cannot resolve symbol pow_di
-    - meson < 1.10
 test:
   imports:
     - scipy
@@ -165,7 +113,6 @@ test:
     - scipy.linalg.interpolative
     - scipy.misc
     - scipy.ndimage
-    - scipy.odr
     - scipy.optimize
     - scipy.signal
     - scipy.signal.windows

packages/scipy/patches/0003-Fix-gees-calls.patch → packages/scipy/patches/0001-Fix-gees-calls.patch

@@ -1,7 +1,7 @@
 From 8addc1da35bc63df651946ef14c723797a431e0c Mon Sep 17 00:00:00 2001
 From: Hood Chatham <roberthoodchatham@gmail.com>
 Date: Mon, 26 Jun 2023 20:12:25 -0700
-Subject: [PATCH 3/6] Fix gees calls
+Subject: [PATCH 1/2] Fix gees calls
 
 ---
  scipy/linalg/flapack_gen.pyf.src | 8 ++++----

packages/scipy/patches/0002-Fix-signatures-for-getrf-getri-and-trlib-dlagtm.patch

@@ -0,0 +1,90 @@
+From af8b0fc9a2164c29cf179e71f6e139406474b89c Mon Sep 17 00:00:00 2001
+From: Agriya Khetarpal <74401230+agriyakhetarpal@users.noreply.github.com>
+Date: Fri, 10 Jul 2026 14:22:09 +0300
+Subject: [PATCH 2/2] Correct `?getrf`/`?getri` return types and `trlib` `dlagtm` ABI for strict-signature toolchains
+
+From https://github.com/scipy/scipy/pull/25592. Drop this with SciPy v1.19
+
+---
+ scipy/linalg/src/_common_array_utils.hh | 16 ++++++++--------
+ scipy/optimize/_trlib/trlib_private.h   |  6 ++++--
+ 2 files changed, 12 insertions(+), 10 deletions(-)
+
+diff --git a/scipy/linalg/src/_common_array_utils.hh b/scipy/linalg/src/_common_array_utils.hh
+index 7b42d4ec18..e1fe742322 100644
+--- a/scipy/linalg/src/_common_array_utils.hh
++++ b/scipy/linalg/src/_common_array_utils.hh
+@@ -15,38 +15,38 @@
+ extern "C" {
+
+ /* ?GETRF */
+-CBLAS_INT
++void
+ BLAS_FUNC(sgetrf)(CBLAS_INT *m, CBLAS_INT *n, float a[], CBLAS_INT *lda,
+                   CBLAS_INT ipiv[], CBLAS_INT *info
+ );
+-CBLAS_INT
++void
+ BLAS_FUNC(dgetrf)(CBLAS_INT *m, CBLAS_INT *n, double a[], CBLAS_INT *lda,
+                   CBLAS_INT ipiv[], CBLAS_INT *info
+ );
+-CBLAS_INT
++void
+ BLAS_FUNC(cgetrf)(CBLAS_INT *m, CBLAS_INT *n, npy_complex64 a[], CBLAS_INT *lda,
+                   CBLAS_INT ipiv[], CBLAS_INT *info
+ );
+-CBLAS_INT
++void
+ BLAS_FUNC(zgetrf)(CBLAS_INT *m, CBLAS_INT *n, npy_complex128 a[], CBLAS_INT *lda,
+                   CBLAS_INT ipiv[], CBLAS_INT *info
+ );
+
+
+ /* ?GETRI */
+-CBLAS_INT
++void
+ BLAS_FUNC(sgetri)(CBLAS_INT *n, float a[], CBLAS_INT *lda, CBLAS_INT ipiv[],
+                   float work[], CBLAS_INT *lwork, CBLAS_INT *info
+ );
+-CBLAS_INT
++void
+ BLAS_FUNC(dgetri)(CBLAS_INT *n, double a[], CBLAS_INT *lda, CBLAS_INT ipiv[],
+                   double work[], CBLAS_INT *lwork, CBLAS_INT *info
+ );
+-CBLAS_INT
++void
+ BLAS_FUNC(cgetri)(CBLAS_INT *n, npy_complex64 a[], CBLAS_INT *lda, CBLAS_INT ipiv[],
+                   npy_complex64 work[], CBLAS_INT *lwork, CBLAS_INT *info
+ );
+-CBLAS_INT
++void
+ BLAS_FUNC(zgetri)(CBLAS_INT *n, npy_complex128 a[], CBLAS_INT *lda, CBLAS_INT ipiv[],
+                   npy_complex128 work[], CBLAS_INT *lwork, CBLAS_INT *info
+ );
+diff --git a/scipy/optimize/_trlib/trlib_private.h b/scipy/optimize/_trlib/trlib_private.h
+index 92bfabe51d..06abcc72f2 100644
+--- a/scipy/optimize/_trlib/trlib_private.h
++++ b/scipy/optimize/_trlib/trlib_private.h
+@@ -49,7 +49,9 @@ double BLAS_FUNC(ddot)(CBLAS_INT *n, double *x, CBLAS_INT *incx, double *y, CBLA
+ void BLAS_FUNC(dpttrf)(CBLAS_INT *n, double *d, double *e, CBLAS_INT *info);
+ void BLAS_FUNC(dpttrs)(CBLAS_INT *n, CBLAS_INT *nrhs, double *d, double *e, double *b, CBLAS_INT *ldb, CBLAS_INT *info);
+ void BLAS_FUNC(dptrfs)(CBLAS_INT *n, CBLAS_INT *nrhs, double *d, double *e, double *df, double *ef, double *b, CBLAS_INT *ldb, double *x, CBLAS_INT *ldx, double *ferr, double *berr, double *work, CBLAS_INT *info);
+-void BLAS_FUNC(dlagtm)(char *trans, CBLAS_INT *n, CBLAS_INT *nrhs, double *alpha, double *dl, double *d, double *du, double *x, CBLAS_INT *ldx, double *beta, double *b, CBLAS_INT *ldb, int);
++// dlagtm is declared without a trailing hidden Fortran
++// string length for trans. See gh-25592.
++void BLAS_FUNC(dlagtm)(char *trans, CBLAS_INT *n, CBLAS_INT *nrhs, double *alpha, double *dl, double *d, double *du, double *x, CBLAS_INT *ldx, double *beta, double *b, CBLAS_INT *ldb);
+
+
+ static void trlib_daxpy(trlib_int_t *n, double *alpha, double *x, trlib_int_t *incx, double *y, trlib_int_t *incy)
+@@ -108,7 +110,7 @@ static void trlib_dlagtm(char *trans, trlib_int_t *n, trlib_int_t *nrhs, double
+                          trlib_int_t *ldx, double *beta, double *b, trlib_int_t *ldb)
+ {
+     CBLAS_INT n_ = *n, nrhs_ = *nrhs, ldb_ = *ldb, ldx_ = *ldx;
+-    BLAS_FUNC(dlagtm)(trans, &n_, &nrhs_, alpha, dl, d, du, x, &ldx_, beta, b, &ldb_, 1);
++    BLAS_FUNC(dlagtm)(trans, &n_, &nrhs_, alpha, dl, d, du, x, &ldx_, beta, b, &ldb_);
+ }
+
+
+-- 
+2.50.1 (Apple Git-155)
+