From a9e14970309c628ca2eaafa886d67c2b96c121f0 Mon Sep 17 00:00:00 2001
From: Radovan Bast <bast@users.noreply.github.com>
Date: Thu, 4 Jun 2015 17:57:18 +0200
Subject: [PATCH] FCFLAGS overrules other flags

---
 compilers/GNU.Fortran.cmake   | 10 ++++++----
 compilers/Intel.Fortran.cmake | 10 ++++++----
 compilers/PGI.Fortran.cmake   | 10 ++++++----
 compilers/XL.Fortran.cmake    | 10 ++++++----
 modules/fc.cmake              | 19 ++++++++++++++-----
 5 files changed, 38 insertions(+), 21 deletions(-)

diff --git a/compilers/GNU.Fortran.cmake b/compilers/GNU.Fortran.cmake
index 9602b22..cab129e 100644
--- a/compilers/GNU.Fortran.cmake
+++ b/compilers/GNU.Fortran.cmake
@@ -1,5 +1,7 @@
-if(CMAKE_Fortran_COMPILER_ID MATCHES GNU)
-    set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS}")
-    set(CMAKE_Fortran_FLAGS_RELEASE "-O3 -funroll-all-loops -w")
-    set(CMAKE_Fortran_FLAGS_DEBUG "-O0 -g -fbacktrace")
+if(NOT DEFINED ENV{FCFLAGS})
+    if(CMAKE_Fortran_COMPILER_ID MATCHES GNU)
+        set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS}")
+        set(CMAKE_Fortran_FLAGS_RELEASE "-O3 -funroll-all-loops -w")
+        set(CMAKE_Fortran_FLAGS_DEBUG "-O0 -g -fbacktrace")
+    endif()
 endif()
diff --git a/compilers/Intel.Fortran.cmake b/compilers/Intel.Fortran.cmake
index 9d753c0..6b4ce35 100644
--- a/compilers/Intel.Fortran.cmake
+++ b/compilers/Intel.Fortran.cmake
@@ -1,5 +1,7 @@
-if(CMAKE_Fortran_COMPILER_ID MATCHES Intel)
-    set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} -w -assume byterecl")
-    set(CMAKE_Fortran_FLAGS_RELEASE "-O3 -ip")
-    set(CMAKE_Fortran_FLAGS_DEBUG "-O0 -g -traceback")
+if(NOT DEFINED ENV{FCFLAGS})
+    if(CMAKE_Fortran_COMPILER_ID MATCHES Intel)
+        set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} -w -assume byterecl")
+        set(CMAKE_Fortran_FLAGS_RELEASE "-O3 -ip")
+        set(CMAKE_Fortran_FLAGS_DEBUG "-O0 -g -traceback")
+    endif()
 endif()
diff --git a/compilers/PGI.Fortran.cmake b/compilers/PGI.Fortran.cmake
index 9648f5f..2c73600 100644
--- a/compilers/PGI.Fortran.cmake
+++ b/compilers/PGI.Fortran.cmake
@@ -1,5 +1,7 @@
-if(CMAKE_Fortran_COMPILER_ID MATCHES PGI)
-    set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS}")
-    set(CMAKE_Fortran_FLAGS_RELEASE "-O3")
-    set(CMAKE_Fortran_FLAGS_DEBUG "-g")
+if(NOT DEFINED ENV{FCFLAGS})
+    if(CMAKE_Fortran_COMPILER_ID MATCHES PGI)
+        set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS}")
+        set(CMAKE_Fortran_FLAGS_RELEASE "-O3")
+        set(CMAKE_Fortran_FLAGS_DEBUG "-g")
+    endif()
 endif()
diff --git a/compilers/XL.Fortran.cmake b/compilers/XL.Fortran.cmake
index cfa260f..23f9a4b 100644
--- a/compilers/XL.Fortran.cmake
+++ b/compilers/XL.Fortran.cmake
@@ -1,5 +1,7 @@
-if(CMAKE_Fortran_COMPILER_ID MATCHES XL)
-    set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} -qzerosize -qextname -qsuppress=cmpmsg")
-    set(CMAKE_Fortran_FLAGS_RELEASE "-O3")
-    set(CMAKE_Fortran_FLAGS_DEBUG "-g")
+if(NOT DEFINED ENV{FCFLAGS})
+    if(CMAKE_Fortran_COMPILER_ID MATCHES XL)
+        set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} -qzerosize -qextname -qsuppress=cmpmsg")
+        set(CMAKE_Fortran_FLAGS_RELEASE "-O3")
+        set(CMAKE_Fortran_FLAGS_DEBUG "-g")
+    endif()
 endif()
diff --git a/modules/fc.cmake b/modules/fc.cmake
index 70c20e0..9280838 100644
--- a/modules/fc.cmake
+++ b/modules/fc.cmake
@@ -1,13 +1,22 @@
 #.rst:
 #
 # Adds Fortran support.
-# Appends EXTRA_Fortran_FLAGS to CMAKE_Fortran_FLAGS.
-# If environment variable FCFLAGS is set, then these flags are used
-# and no other flags are appended.
+# Appends EXTRA_FCFLAGS to CMAKE_Fortran_FLAGS.
+# If environment variable FCFLAGS is set, then the FCFLAGS are used
+# and no other flags are used or appended.
 #
 # Defines::
 #
 #   CMAKE_Fortran_MODULE_DIRECTORY (${PROJECT_BINARY_DIR}/include/fortran)
+#
+# Example autocmake.cfg entry::
+#
+#   [fc]
+#   source: https://github.com/scisoft/autocmake/raw/master/modules/fc.cmake
+#   docopt: --fc=<FC> Fortran compiler [default: gfortran].
+#           --extra-fc-flags=<EXTRA_FCFLAGS> Extra Fortran compiler flags [default: ''].
+#   export: 'FC=%s' % arguments['--fc']``
+#   define: '-DEXTRA_FCFLAGS=%s' % arguments['--extra-fc-flags']
 
 enable_language(Fortran)
 
@@ -21,8 +30,8 @@ if(NOT CMAKE_Fortran_COMPILER_WORKS)
     message(FATAL_ERROR "CMAKE_Fortran_COMPILER_WORKS is false!")
 endif()
 
-if(DEFINED EXTRA_Fortran_FLAGS)
-    set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} ${EXTRA_Fortran_FLAGS}")
+if(DEFINED EXTRA_FCFLAGS)
+    set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} ${EXTRA_FCFLAGS}")
 endif()
 
 if(DEFINED ENV{FCFLAGS})