submodule procedures declaration made compatible with older cmake version

STYLE_GUIDE.md

@@ -61,7 +61,15 @@ focus on the semantics of the proposed changes rather than style and formatting.
   ```  
   When defining many arrays of the same dimension, `dimension` can be used as an exception if it makes the code less verbose.
 * If the `optional` attribute is used to declare a dummy argument, it should follow the `intent` attribute.
-
+* For module procedures, it is recommended to declare attributes before the module keyword for better retro compatibility (Projects using CMake versions lower than CMake 3.25.0 are concerned see [Spurious modules](https://gitlab.kitware.com/cmake/cmake/-/issues/18427#note_983426)).
+  Prefer the following pattern:
+  ```
+  <attribute> <attribute> module <function/subroutine> <name>
+  ```
+  instead of:
+  ```
+  module <attribute> <attribute> <function/subroutine> <name>
+  ```
 ## End <scope> block closing statements
 
 Fortran allows certain block constructs or scopes to include the name of the program unit in the end statement.

src/stdlib_linalg.fypp

@@ -154,13 +154,13 @@ module stdlib_linalg
       ! Vector to matrix
       !
     #:for k1, t1 in RCI_KINDS_TYPES
-      module pure function diag_${t1[0]}$${k1}$(v) result(res)
+      pure module function diag_${t1[0]}$${k1}$(v) result(res)
         ${t1}$, intent(in) :: v(:)
         ${t1}$ :: res(size(v),size(v))
       end function diag_${t1[0]}$${k1}$
     #:endfor
     #:for k1, t1 in RCI_KINDS_TYPES
-      module pure function diag_${t1[0]}$${k1}$_k(v,k) result(res)
+      pure module function diag_${t1[0]}$${k1}$_k(v,k) result(res)
         ${t1}$, intent(in) :: v(:)
         integer, intent(in) :: k
         ${t1}$ :: res(size(v)+abs(k),size(v)+abs(k))
@@ -171,13 +171,13 @@ module stdlib_linalg
       ! Matrix to vector
       !
     #:for k1, t1 in RCI_KINDS_TYPES
-      module pure function diag_${t1[0]}$${k1}$_mat(A) result(res)
+      pure module function diag_${t1[0]}$${k1}$_mat(A) result(res)
         ${t1}$, intent(in) :: A(:,:)
         ${t1}$ :: res(minval(shape(A)))
       end function diag_${t1[0]}$${k1}$_mat
     #:endfor
     #:for k1, t1 in RCI_KINDS_TYPES
-      module pure function diag_${t1[0]}$${k1}$_mat_k(A,k) result(res)
+      pure module function diag_${t1[0]}$${k1}$_mat_k(A,k) result(res)
         ${t1}$, intent(in) :: A(:,:)
         integer, intent(in) :: k
         ${t1}$ :: res(minval(shape(A))-abs(k))

src/stdlib_linalg_diag.fypp

@@ -7,7 +7,7 @@ submodule (stdlib_linalg) stdlib_linalg_diag
 contains
 
     #:for k1, t1 in RCI_KINDS_TYPES
-      module pure function diag_${t1[0]}$${k1}$(v) result(res)
+      pure module function diag_${t1[0]}$${k1}$(v) result(res)
         ${t1}$, intent(in) :: v(:)
         ${t1}$ :: res(size(v),size(v))
         integer :: i
@@ -20,7 +20,7 @@ contains
 
 
     #:for k1, t1 in RCI_KINDS_TYPES
-      module pure function diag_${t1[0]}$${k1}$_k(v,k) result(res)
+      pure module function diag_${t1[0]}$${k1}$_k(v,k) result(res)
         ${t1}$, intent(in) :: v(:)
         integer, intent(in) :: k
         ${t1}$ :: res(size(v)+abs(k),size(v)+abs(k))
@@ -44,7 +44,7 @@ contains
     #:endfor
 
     #:for k1, t1 in RCI_KINDS_TYPES
-      module pure function diag_${t1[0]}$${k1}$_mat(A) result(res)
+      pure module function diag_${t1[0]}$${k1}$_mat(A) result(res)
         ${t1}$, intent(in) :: A(:,:)
         ${t1}$ :: res(minval(shape(A)))
         integer :: i
@@ -55,7 +55,7 @@ contains
     #:endfor
 
     #:for k1, t1 in RCI_KINDS_TYPES
-      module pure function diag_${t1[0]}$${k1}$_mat_k(A,k) result(res)
+      pure module function diag_${t1[0]}$${k1}$_mat_k(A,k) result(res)
         ${t1}$, intent(in) :: A(:,:)
         integer, intent(in) :: k
         ${t1}$ :: res(minval(shape(A))-abs(k))

src/stdlib_system.F90

@@ -500,7 +500,7 @@ end function run_sync_args
     !!
     !! @note The implementation relies on system-level process management capabilities.
     !!
-    module logical function process_is_running(process) result(is_running)
+    logical module function process_is_running(process) result(is_running)
         !> The process object to check.
         class(process_type), intent(inout) :: process
         !> Logical result: `.true.` if the process is still running, `.false.` otherwise.
@@ -524,7 +524,7 @@ end function process_is_running
     !!
     !! @note The implementation relies on system-level process management capabilities.
     !!
-    module logical function process_is_completed(process) result(is_completed)
+    logical module function process_is_completed(process) result(is_completed)
         !> The process object to check.
         class(process_type), intent(inout) :: process
         !> Logical result: `.true.` if the process has completed, `.false.` otherwise.
@@ -711,7 +711,7 @@ end subroutine process_callback
     !!
     !! @note This function relies on the `_WIN32` macro, which is defined in C compilers when targeting Windows.
     !!
-    module logical function is_windows()
+    logical module function is_windows()
     end function is_windows
 
     module function process_get_ID(process) result(ID)

src/stdlib_system_subprocess.F90

@@ -331,7 +331,7 @@ subroutine launch_synchronous(process, args, stdin)
     end subroutine launch_synchronous
 
     !> Return the current (or total) process lifetime, in seconds
-    module real(RTICKS) function process_lifetime(process) result(delta_t)
+    real(RTICKS) module function process_lifetime(process) result(delta_t)
         class(process_type), intent(in) :: process 
 
         real(RTICKS) :: ticks_per_second
@@ -511,7 +511,7 @@ subroutine save_completed_state(process,delete_files)
     end subroutine save_completed_state
 
     !> Live check if a process is running
-    module logical function process_is_running(process) result(is_running)
+    logical module function process_is_running(process) result(is_running)
         class(process_type), intent(inout) :: process
 
         ! Each evaluation triggers a state update
@@ -522,7 +522,7 @@ module logical function process_is_running(process) result(is_running)
     end function process_is_running
 
     !> Live check if a process has completed
-    module logical function process_is_completed(process) result(is_completed)
+    logical module function process_is_completed(process) result(is_completed)
         class(process_type), intent(inout) :: process
 
         ! Each evaluation triggers a state update
@@ -600,7 +600,7 @@ end function assemble_cmd
     !> Returns the file path of the null device for the current operating system.
     !>
     !> Version: Helper function.
-    module logical function is_windows()
+    logical module function is_windows()
        is_windows = logical(process_is_windows())
     end function is_windows