numpy · charris · Jul 21, 2021 · Feb 4, 2021 · Apr 15, 2021 · Apr 25, 2021
diff --git a/.github/workflows/cygwin.yml b/.github/workflows/cygwin.yml
@@ -0,0 +1,67 @@
+name: Test on Cygwin
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+jobs:
+  cygwin_build_test:
+    runs-on: windows-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          submodules: recursive
+          fetch-depth: 0
+      - name: Install Cygwin
+        uses: egor-tensin/setup-cygwin@v3
+        with:
+          platform: x64
+          install-dir: 'C:\tools\cygwin'
+          packages: >
+            python37-devel python37-zipp python37-importlib-metadata
+            python37-cython python37-pip python37-wheel python37-cffi
+            python37-pytz python37-setuptools python37-pytest
+            python37-hypothesis liblapack-devel libopenblas
+            gcc-fortran git dash
+      - name: Set Windows PATH
+        uses: egor-tensin/cleanup-path@v1
+        with:
+          dirs: 'C:\tools\cygwin\bin;C:\tools\cygwin\lib\lapack'
+      - name: Verify that bash is Cygwin bash
+        run: |
+          command bash
+          bash -c "uname -svrmo"
+      - name: Update with Cygwin git
+        # fetch-depth=0 above should make this short.
+        run: |
+          dash -c "which git; /usr/bin/git fetch --all -p"
+      - name: Verify python version
+        # Make sure it's the Cygwin one, not a Windows one
+        run: |
+          dash -c "which python3.7; /usr/bin/python3.7 --version -V"
+      - name: Build NumPy wheel
+        run: |
+          dash -c "/usr/bin/python3.7 -m pip install 'setuptools<49.2.0' pytest pytz cffi pickle5 importlib_metadata typing_extensions"
+          dash -c "/usr/bin/python3.7 -m pip install -r test_requirements.txt"
+          dash -c "/usr/bin/python3.7 setup.py bdist_wheel"
+      - name: Install new NumPy
+        run: |
+          bash -c "/usr/bin/python3.7 -m pip install dist/numpy-*cp37*.whl"
+      - name: Run NumPy test suite
+        run: >-
+          dash -c "/usr/bin/python3.7 runtests.py -n -vv"
+      - name: Upload wheel if tests fail
+        uses: actions/upload-artifact@v2
+        if: failure()
+        with:
+          name: numpy-cygwin-wheel
+          path: dist/numpy-*cp37*.whl
+      - name: On failure check the extension modules
+        if: failure()
+        run: |
+          dash -c "/usr/bin/python3.7 -m pip show numpy"
+          dash -c "/usr/bin/python3.7 -m pip show -f numpy | grep .dll"
+          dash -c "/bin/tr -d '\r' <tools/list_installed_dll_dependencies_cygwin.sh >list_dlls_unix.sh"
+          dash "list_dlls_unix.sh"
diff --git a/numpy/core/include/numpy/random/distributions.h b/numpy/core/include/numpy/random/distributions.h
@@ -28,7 +28,7 @@ extern "C" {
 #define RAND_INT_MAX INT64_MAX
 #endif
 
-#ifdef _MSC_VER
+#if defined(_MSC_VER) || defined(__CYGWIN__)
 #define DECLDIR __declspec(dllexport)
 #else
 #define DECLDIR extern

diff --git a/numpy/core/src/common/npy_config.h b/numpy/core/src/common/npy_config.h
@@ -96,6 +96,51 @@
 #undef HAVE_POWL
 #endif
 
+#ifdef __CYGWIN__
+/* Loss of precision */
+#undef HAVE_CASINHL
+#undef HAVE_CASINH
+#undef HAVE_CASINHF
+
+/* Loss of precision */
+#undef HAVE_CATANHL
+#undef HAVE_CATANH
+#undef HAVE_CATANHF
+
+/* Loss of precision and branch cuts */
+#undef HAVE_CATANL
+#undef HAVE_CATAN
+#undef HAVE_CATANF
+
+/* Branch cuts */
+#undef HAVE_CACOSHF
+#undef HAVE_CACOSH
+
+/* Branch cuts */
+#undef HAVE_CSQRTF
+#undef HAVE_CSQRT
+
+/* Branch cuts and loss of precision */
+#undef HAVE_CASINF
+#undef HAVE_CASIN
+#undef HAVE_CASINL
+
+/* Branch cuts */
+#undef HAVE_CACOSF
+#undef HAVE_CACOS
+
+/* log2(exp2(i)) off by a few eps */
+    #undef HAVE_LOG2
+
+/* np.power(..., dtype=np.complex256) doesn't report overflow */
+#undef HAVE_CPOWL
+#undef HAVE_CEXPL
+
+/* Builtin abs reports overflow */
+#undef HAVE_CABSL
+#undef HAVE_HYPOTL
+#endif
+
 /* Disable broken gnu trig functions */
 #if defined(HAVE_FEATURES_H)
 #include <features.h>

diff --git a/numpy/core/tests/test_scalarmath.py b/numpy/core/tests/test_scalarmath.py
@@ -680,10 +680,18 @@ def _test_abs_func(self, absfunc, test_dtype):
 
     @pytest.mark.parametrize("dtype", floating_types + complex_floating_types)
     def test_builtin_abs(self, dtype):
+        if sys.platform == "cygwin" and dtype == np.clongdouble:
+            pytest.xfail(
+                reason="absl is computed in double precision on cygwin"
+            )
         self._test_abs_func(abs, dtype)
 
     @pytest.mark.parametrize("dtype", floating_types + complex_floating_types)
     def test_numpy_abs(self, dtype):
+        if sys.platform == "cygwin" and dtype == np.clongdouble:
+            pytest.xfail(
+                reason="absl is computed in double precision on cygwin"
+            )
         self._test_abs_func(np.abs, dtype)
 
 class TestBitShifts:

diff --git a/tools/list_installed_dll_dependencies_cygwin.sh b/tools/list_installed_dll_dependencies_cygwin.sh
@@ -0,0 +1,38 @@
+#!/bin/dash
+# Check permissions and dependencies on installed DLLs
+# DLLs need execute permissions to be used
+# DLLs must be able to find their dependencies
+# This checks both of those, then does a direct test
+# The best way of checking whether a C extension module is importable
+# is trying to import it.  The rest is trying to give reasons why it
+# isn't importing.
+#
+# One of the tools and the extension for shared libraries are
+# Cygwin-specific, but the rest should work on most platforms with
+# /bin/sh
+
+py_ver=3.7
+site_packages=$(python${py_ver} -m pip show numpy | \
+		    grep Location | cut -d " " -f 2 -);
+dll_list=$(for name in $(python${py_ver} -m pip show -f numpy | \
+			     grep -F .dll); do echo ${site_packages}/${name}; done)
+echo "Checks for existence, permissions and file type"
+ls -l ${dll_list}
+file ${dll_list}
+echo "Dependency checks"
+ldd ${dll_list} | grep -F -e " => not found" && exit 1
+cygcheck ${dll_list} >cygcheck_dll_list 2>cygcheck_missing_deps
+grep -F -e "cygcheck: track_down: could not find " cygcheck_missing_deps && exit 1
+echo "Import tests"
+mkdir -p dist/
+cd dist/
+for name in ${dll_list};
+do
+    echo ${name}
+    ext_module=$(echo ${name} | \
+                     sed -E \
+			 -e "s/^\/+(home|usr).*?site-packages\/+//" \
+			 -e "s/.cpython-3.m?-x86(_64)?-cygwin.dll$//" \
+			 -e "s/\//./g")
+    python${py_ver} -c "import ${ext_module}"
+done