Merge pull request #1256 from ACSimon33/intel_compilers_on_windows

Fixes for Intel compilers on Windows

CBLAS/CMakeLists.txt

@@ -13,9 +13,16 @@ endif()
 
 set(LAPACK_INSTALL_EXPORT_NAME ${CBLASLIB}-targets)
 
-include(CheckCSourceCompiles)
-check_c_source_compiles("int __attribute__((weak)) main() {};"
-                        HAS_ATTRIBUTE_WEAK_SUPPORT)
+if(WIN32)
+  # MSVC does not support __attribute__((weak)) and the Intel compiler supports
+  # it but produces linker errors when used in CBLAS, so we disable it for all
+  # Windows builds.
+  set(HAS_ATTRIBUTE_WEAK_SUPPORT FALSE)
+else()
+  include(CheckCSourceCompiles)
+  check_c_source_compiles("int __attribute__((weak)) main() {};"
+                          HAS_ATTRIBUTE_WEAK_SUPPORT)
+endif()
 
 include_directories(include ${LAPACK_BINARY_DIR}/include)
 add_subdirectory(src)

LAPACKE/include/lapack.h

@@ -47,7 +47,8 @@
 #else
 #include <complex>
 #endif
-#if _MSC_VER
+
+#if defined(_MSC_VER) && !defined(__INTEL_COMPILER) && !defined(__INTEL_LLVM_COMPILER)
 #define lapack_complex_float    _Fcomplex
 #else
 #define lapack_complex_float    float _Complex
@@ -69,7 +70,8 @@
 #else
 #include <complex>
 #endif
-#if _MSC_VER
+
+#if defined(_MSC_VER) && !defined(__INTEL_COMPILER) && !defined(__INTEL_LLVM_COMPILER)
 #define lapack_complex_double   _Dcomplex
 #else
 #define lapack_complex_double   double _Complex

LAPACKE/include/lapacke_config.h

@@ -99,7 +99,7 @@ typedef struct { double real, imag; } _lapack_complex_double;
 #define lapack_complex_double_real(z)       ((z).real())
 #define lapack_complex_double_imag(z)       ((z).imag())
 
-#elif _MSC_VER
+#elif defined(_MSC_VER) && !defined(__INTEL_COMPILER) && !defined(__INTEL_LLVM_COMPILER)
 
 #include <complex.h>
 #define lapack_complex_float    _Fcomplex

LAPACKE/utils/lapacke_make_complex_double.c

@@ -43,7 +43,7 @@ lapack_complex_double lapack_make_complex_double( double re, double im ) {
     z = re + im * I;
 #elif defined(LAPACK_COMPLEX_CPP)
     z = std::complex<double>(re,im);
-#elif _MSC_VER
+#elif defined(_MSC_VER) && !defined(__INTEL_COMPILER) && !defined(__INTEL_LLVM_COMPILER)
     z = _Cbuild(re, im);
 #else /* C99 is default */
     z = re + im*I;

LAPACKE/utils/lapacke_make_complex_float.c

@@ -43,7 +43,7 @@ lapack_complex_float lapack_make_complex_float( float re, float im ) {
     z = re + im * I;
 #elif defined(LAPACK_COMPLEX_CPP)
     z = std::complex<float>(re,im);
-#elif _MSC_VER
+#elif defined(_MSC_VER) && !defined(__INTEL_COMPILER) && !defined(__INTEL_LLVM_COMPILER)
     z = _FCbuild(re, im);
 #else /* C99 is default */
     z = re + im*I;