new test: package depends on empty library

Author: perazz

example_packages/shared_lib_empty/fpm.toml

@@ -0,0 +1,5 @@
+name = "shared_lib_extra"
+library.type="shared"
+[dependencies]
+shared_lib = { path = "../shared_lib" }
+shared_app_only = { path = "../shared_app_only" }

src/fpm_model.f90

@@ -174,6 +174,9 @@ module fpm_model
 
     contains
 
+        !> Check if a package will create a library
+        procedure :: has_library => package_has_library
+    
         !> Serialization interface
         procedure :: serializable_is_same => package_is_same
         procedure :: dump_to_toml   => package_dump_to_toml
@@ -1153,6 +1156,7 @@ function get_package_libraries_link(model, package_name, prefix, exclude_self, d
     integer :: id,ndep,i
     logical :: no_root
     integer, allocatable :: sorted_package_IDs(:)
+    logical, allocatable :: empty_package(:)
     type(string_t), allocatable :: package_deps(:)
 
     ! Get dependency ID of this target 
@@ -1184,6 +1188,14 @@ function get_package_libraries_link(model, package_name, prefix, exclude_self, d
         ndep = size(sorted_package_IDs)
     endif
 
+    ! Exclusion of package IDs marked "empty" (i.e. they contain no sources)
+    empty_package = .not.model%packages%has_library()
+    
+    if (any(empty_package)) then 
+        sorted_package_IDs = pack(sorted_package_IDs, .not.empty_package(sorted_package_IDs))
+        ndep = size(sorted_package_IDs)
+    end if
+    
     package_deps = [(string_t(model%deps%dep(sorted_package_IDs(i))%name),i=1,ndep)]
 
     r = model%compiler%enumerate_libraries(prefix, package_deps)
@@ -1193,4 +1205,17 @@ function get_package_libraries_link(model, package_name, prefix, exclude_self, d
 
 end function get_package_libraries_link
 
+!> Check whether a package has an object library
+elemental logical function package_has_library(self) result(has_library)
+    class(package_t), intent(in) :: self
+    
+    if (allocated(self%sources)) then 
+        has_library = any(self%sources%unit_scope==FPM_SCOPE_LIB)
+    else
+        has_library = .false.
+    end if
+    
+end function package_has_library
+
+
 end module fpm_model

src/fpm_targets.f90

@@ -321,9 +321,7 @@ subroutine build_target_list(targets,model,library)
 
     if (n_source < 1) return
 
-    with_lib = any([((model%packages(j)%sources(i)%unit_scope == FPM_SCOPE_LIB, &
-                      i=1,size(model%packages(j)%sources)), &
-                      j=1,size(model%packages))])
+    with_lib = any(model%packages%has_library())
 
     if (with_lib .and. present(library)) then 
         shared_lib = library%shared()
@@ -861,27 +859,32 @@ subroutine prune_build_targets(targets, root_package, prune_unused_objects)
 
     targets = pack(targets,.not.exclude_target)
 
-    ! Remove unused targets from archive dependency list
-    if (targets(1)%ptr%target_type == FPM_TARGET_ARCHIVE) then
-        associate(archive=>targets(1)%ptr)
+    ! Remove unused targets from library dependency list
+    do j=1,size(targets)
+        associate(archive=>targets(j)%ptr)
+            
+            if (any(archive%target_type==[FPM_TARGET_ARCHIVE,FPM_TARGET_OBJECT])) then 
 
-            allocate(exclude_from_archive(size(archive%dependencies)))
-            exclude_from_archive(:) = .false.
+                allocate(exclude_from_archive(size(archive%dependencies)),source=.false.)
 
-            do i=1,size(archive%dependencies)
+                do i=1,size(archive%dependencies)
 
-                if (archive%dependencies(i)%ptr%skip) then
+                    if (archive%dependencies(i)%ptr%skip) then
 
-                    exclude_from_archive(i) = .true.
+                        exclude_from_archive(i) = .true.
 
-                end if
+                    end if
 
-            end do
+                end do
 
-            archive%dependencies = pack(archive%dependencies,.not.exclude_from_archive)
+                archive%dependencies = pack(archive%dependencies,.not.exclude_from_archive)
+                
+                deallocate(exclude_from_archive)
+            
+            endif
 
         end associate
-    end if
+    end do
 
     contains