From edcf4c135f75e1de9fddc536adaa7b8578addc47 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Antonio=20S=C3=A1nchez?= <cantonios@google.com>
Date: Mon, 4 Aug 2025 19:11:43 +0000
Subject: [PATCH] Remove fortran dependency for eigenblas.

---
 blas/CMakeLists.txt         | 19 +---------------
 blas/fortran/complexdots.f  | 43 -------------------------------------
 blas/testing/CMakeLists.txt | 12 +++++++++++
 3 files changed, 13 insertions(+), 61 deletions(-)
 delete mode 100644 blas/fortran/complexdots.f

diff --git a/blas/CMakeLists.txt b/blas/CMakeLists.txt
index 4ae060302..4f189925a 100644
--- a/blas/CMakeLists.txt
+++ b/blas/CMakeLists.txt
@@ -2,14 +2,6 @@
 project(EigenBlas CXX)
 
 if(EIGEN_BUILD_BLAS)
-include(CheckLanguage)
-check_language(Fortran)
-if(CMAKE_Fortran_COMPILER)
-  enable_language(Fortran)
-  set(EIGEN_Fortran_COMPILER_WORKS ON)
-else()
-  set(EIGEN_Fortran_COMPILER_WORKS OFF)
-endif()
 
 add_custom_target(blas)
 
@@ -18,15 +10,9 @@ set(EigenBlas_SRCS  single.cpp double.cpp complex_single.cpp complex_double.cpp
                     f2c/lsame.c   f2c/dspmv.c   f2c/ssbmv.c f2c/chbmv.c
                     f2c/sspmv.c   f2c/zhbmv.c   f2c/chpmv.c f2c/dsbmv.c
                     f2c/zhpmv.c   f2c/dtbmv.c   f2c/stbmv.c f2c/ctbmv.c
-                    f2c/ztbmv.c
+                    f2c/ztbmv.c   f2c/complexdots.c
    )
 
-if (EIGEN_Fortran_COMPILER_WORKS)
-  set(EigenBlas_SRCS ${EigenBlas_SRCS} fortran/complexdots.f)
-else()
-  set(EigenBlas_SRCS ${EigenBlas_SRCS} f2c/complexdots.c)
-endif()
-
 set(EIGEN_BLAS_TARGETS "")
 
 add_library(eigen_blas_static ${EigenBlas_SRCS})
@@ -49,8 +35,6 @@ foreach(target IN LISTS EIGEN_BLAS_TARGETS)
           ARCHIVE DESTINATION lib)
 endforeach()
 
-if(EIGEN_Fortran_COMPILER_WORKS)
-
 if(EIGEN_BUILD_TESTING)
   if(EIGEN_LEAVE_TEST_IN_ALL_TARGET)
     add_subdirectory(testing) # can't do EXCLUDE_FROM_ALL here, breaks CTest
@@ -60,4 +44,3 @@ if(EIGEN_BUILD_TESTING)
 endif()
 
 endif()
-endif()
diff --git a/blas/fortran/complexdots.f b/blas/fortran/complexdots.f
deleted file mode 100644
index a7da51d16..000000000
--- a/blas/fortran/complexdots.f
+++ /dev/null
@@ -1,43 +0,0 @@
-      COMPLEX FUNCTION CDOTC(N,CX,INCX,CY,INCY)
-      INTEGER INCX,INCY,N
-      COMPLEX CX(*),CY(*)
-      COMPLEX RES
-      EXTERNAL CDOTCW
-      
-      CALL CDOTCW(N,CX,INCX,CY,INCY,RES)
-      CDOTC = RES
-      RETURN
-      END
-      
-      COMPLEX FUNCTION CDOTU(N,CX,INCX,CY,INCY)
-      INTEGER INCX,INCY,N
-      COMPLEX CX(*),CY(*)
-      COMPLEX RES
-      EXTERNAL CDOTUW
-      
-      CALL CDOTUW(N,CX,INCX,CY,INCY,RES)
-      CDOTU = RES
-      RETURN
-      END
-      
-      DOUBLE COMPLEX FUNCTION ZDOTC(N,CX,INCX,CY,INCY)
-      INTEGER INCX,INCY,N
-      DOUBLE COMPLEX CX(*),CY(*)
-      DOUBLE COMPLEX RES
-      EXTERNAL ZDOTCW
-      
-      CALL ZDOTCW(N,CX,INCX,CY,INCY,RES)
-      ZDOTC = RES
-      RETURN
-      END
-      
-      DOUBLE COMPLEX FUNCTION ZDOTU(N,CX,INCX,CY,INCY)
-      INTEGER INCX,INCY,N
-      DOUBLE COMPLEX CX(*),CY(*)
-      DOUBLE COMPLEX RES
-      EXTERNAL ZDOTUW
-      
-      CALL ZDOTUW(N,CX,INCX,CY,INCY,RES)
-      ZDOTU = RES
-      RETURN
-      END
diff --git a/blas/testing/CMakeLists.txt b/blas/testing/CMakeLists.txt
index 52c23acda..f0ee6a487 100644
--- a/blas/testing/CMakeLists.txt
+++ b/blas/testing/CMakeLists.txt
@@ -1,3 +1,13 @@
+include(CheckLanguage)
+check_language(Fortran)
+if(CMAKE_Fortran_COMPILER)
+  enable_language(Fortran)
+  set(EIGEN_Fortran_COMPILER_WORKS ON)
+else()
+  set(EIGEN_Fortran_COMPILER_WORKS OFF)
+endif()
+
+if (EIGEN_Fortran_COMPILER_WORKS)
 
 macro(ei_add_blas_test testname)
 
@@ -38,3 +48,5 @@ ei_add_blas_test(zblat3)
 # add_custom_target(level1)
 # add_dependencies(level1 sblat1)
 
+endif()
+