WIP: patch OpenBLAS build for quadmath symbols

.github/workflows/windows.yml

@@ -45,13 +45,14 @@ jobs:
           echo "PLAT=i686" >> $env:GITHUB_ENV
           echo "WHEEL_PLAT=win32" >> $env:GITHUB_ENV
           echo "MSYSTEM=MINGW32" >> $env:GITHUB_ENV
-          echo "LDFLAGS=-static -static-libgcc" >> $env:GITHUB_ENV
+          # No ucrt on 32-bits, so use _snprintf_c instead
+          echo "LDFLAGS=-static -static-libgcc -Wl,--defsym,_quadmath_snprintf=__snprintf_c" >> $env:GITHUB_ENV
           echo "BUILD_BITS=32" >> $env:GITHUB_ENV
         } else {
           echo "PLAT=x86_64" >> $env:GITHUB_ENV
           echo "WHEEL_PLAT=win_amd64" >> $env:GITHUB_ENV
           echo "MSYSTEM=UCRT64" >> $env:GITHUB_ENV
-          echo "LDFLAGS=-lucrt -static -static-libgcc" >> $env:GITHUB_ENV
+          echo "LDFLAGS=-lucrt -static -static-libgcc -Wl,--defsym,quadmath_snprintf=snprintf" >> $env:GITHUB_ENV
           echo "BUILD_BITS=64" >> $env:GITHUB_ENV
         }
         if ( ${{ matrix.INTERFACE64 }} -eq "1" ) {

patches-windows/openblas-make-libs.patch

@@ -0,0 +1,15 @@
+diff --git a/exports/Makefile b/exports/Makefile
+index 668a4866e..956b51bf4 100644
+--- a/exports/Makefile
++++ b/exports/Makefile
+@@ -126,8 +126,9 @@ dll  : ../$(LIBDLLNAME)
+ ../$(LIBDLLNAME) : ../$(LIBNAME) $(LIBPREFIX).def dllinit.$(SUFFIX)
+ 	$(RANLIB) ../$(LIBNAME)
+ 	$(CC) $(CFLAGS) $(LDFLAGS) $(LIBPREFIX).def dllinit.$(SUFFIX) \
+-	-shared -o ../$(LIBDLLNAME) -Wl,--out-implib,../$(IMPLIBNAME) \
++	-shared -o ../$(LIBDLLNAME) -Wl,-gc-sections -Wl,-s -Wl,-Map,output.map \
+ 	-Wl,--whole-archive ../$(LIBNAME) -Wl,--no-whole-archive $(FEXTRALIB) $(EXTRALIB)
++	dlltool -D $(LIBDLLNAME) -d $(LIBPREFIX).def -l ../$(LIBDLLNAME).a
+
+ $(LIBPREFIX).def : $(GENSYM)
+ 	./$(GENSYM) win2k    $(ARCH) dummy $(EXPRECISION) $(NO_CBLAS) $(NO_LAPACK) $(NO_LAPACKE) $(NEED2UNDERSCORES) $(ONLY_CBLAS) "$(SYMBOLPREFIX)" "$(SYMBOLSUFFIX)" $(BUILD_LAPACK_DEPRECATED) $(BUILD_BFLOAT16) $(BUILD_SINGLE) $(BUILD_DOUBLE) $(BUILD_COMPLEX) $(BUILD_COMPLEX16) > $(@F)

tools/build_openblas.sh

@@ -76,7 +76,7 @@ fflags="$fextra $cflags -frecursive -ffpe-summary=invalid,zero"
 
 # Set suffixed-ILP64 flags
 if [ "$if_bits" == "64" ]; then
-    SYMBOLSUFFIX="64_"
+    LIBNAMESUFFIX="64_"
     interface_flags="INTERFACE64=1 SYMBOLSUFFIX=64_ LIBNAMESUFFIX=64_"
     # We override FCOMMON_OPT, so we need to set default integer manually
     fflags="$fflags -fdefault-integer-8"
@@ -90,8 +90,12 @@ interface_flags="$interface_flags SYMBOLPREFIX=scipy_ LIBNAMEPREFIX=scipy_ FIXED
 # Build name for output library from gcc version and OpenBLAS commit.
 GCC_TAG="gcc_$(gcc -dumpversion | tr .- _)"
 OPENBLAS_VERSION=$(git describe --tags --abbrev=8)
+
+# Patch OpenBLAS build to resolve all symbols and avoid linking
+# with libquadmath
+patch -p1 < ../patches-windows/openblas-make-libs.patch
+
 # Build OpenBLAS
-# Variable used in creating output libraries
 make BINARY=$build_bits DYNAMIC_ARCH=1 USE_THREAD=1 USE_OPENMP=0 \
      NUM_THREADS=24 NO_WARMUP=1 NO_AFFINITY=1 CONSISTENT_FPCSR=1 \
      BUILD_LAPACK_DEPRECATED=1 TARGET=PRESCOTT BUFFERSIZE=20\
@@ -100,8 +104,38 @@ make BINARY=$build_bits DYNAMIC_ARCH=1 USE_THREAD=1 USE_OPENMP=0 \
      FCOMMON_OPT="$fflags" \
      MAX_STACK_ALLOC=2048 \
      $interface_flags
+
+# Make sure quadmath library is not statically linked in to the DLL by checking
+# the output.map generated by the linker when using `-Wl,-gc-sections -Wl,-s`
+# the map will have libname(o-filename) for each function pulled out of the
+# library libname
+# The file itself appears in the map, so look for "libquadmath.a(". Use '-A 3'
+# to show a bit of context if any symbols appear (which should not happen)
+set +e
+grep -A 2 "libquadmath.a(" exports/output.map
+case $? in
+  0)
+    echo "link uses libquadmath.a when it should not"
+    exit -1
+  ;;
+  1)
+    if [ -f exports/output.map ]; then
+      echo "Good, verified no 'libquadmath' used when linking"
+    else
+      echo "error occurred"
+      exit -1
+    fi
+  ;;
+  *)
+    echo "grep returned $?, error occurred"
+    exit -1
+  ;;
+esac
+set -e
+
 make PREFIX=$openblas_root/$build_bits $interface_flags install
-DLL_BASENAME=libscipy_openblas${SYMBOLSUFFIX}${LIBNAMESUFFIX}
+DLL_BASENAME=libscipy_openblas${LIBNAMESUFFIX}
+cp -f *.dll.a $openblas_root/$build_bits/lib/${DLL_BASENAME}.dll.a
 
 # OpenBLAS does not build a symbol-suffixed static library on Windows:
 # do it ourselves. On 32-bit builds, the objcopy.def names need a '_' prefix
@@ -143,16 +177,8 @@ else
     sed -e "s/^Cflags.*/\0 -DBLAS_SYMBOL_PREFIX=scipy_/" -i pkgconfig/scipy-openblas.pc
 fi
 popd
-# Build template site.cfg for using this build
-cat > ${build_bits}/site.cfg.template << EOF
-[openblas${SYMBOLSUFFIX}]
-libraries = $DLL_BASENAME
-library_dirs = {openblas_root}\\${build_bits}\\lib
-include_dirs = {openblas_root}\\${build_bits}\\include
-EOF
-
 ls $openblas_root/$build_bits/lib
 
-zip_name="openblas${SYMBOLSUFFIX}-${OPENBLAS_VERSION}-${plat_tag}-${GCC_TAG}.zip"
+zip_name="openblas${LIBNAMESUFFIX}-${OPENBLAS_VERSION}-${plat_tag}-${GCC_TAG}.zip"
 zip -r $zip_name $build_bits
 cp $zip_name ${builds_dir}

tools/windows_build.bat

@@ -0,0 +1,14 @@
+rem Build x86_64 OpenBLAS locally with 64-bit interfaces
+rem Requires c:\rtools40
+set BASH_PATH=c:\rtools40\usr\bin\bash.exe
+set BUILD_BITS=64
+set CHERE_INVOKING=yes
+set INTERFACE64=1
+set LDFLAGS=-lucrt -static -static-libgcc -Wl,--defsym,quadmath_snprintf=snprintf
+set MSYSTEM=UCRT64
+set PLAT=x86_64
+set START_DIR=d:\pypy_stuff\openblas-libs
+set OPENBLAS_ROOT=c:\\opt
+rmdir /q /s c:\opt\64
+rem %BASH_PATH% -lc tools/build_openblas.sh
+rem %BASH_PATH% -lc tools/build_gfortran.sh