fix: complete deallocate audit for m_ibm and add lint check

- m_ibm: add @:DEALLOCATE for ghost_points, simplify models
  deallocation, replace plain deallocate for recv_* arrays
- lint_source.py: add check_allocate_deallocate_pairing() to
  flag @:ALLOCATE without matching @:DEALLOCATE anywhere in src/
  Known program-lifetime exemptions are listed explicitly

Closes #1459

Author: SVS87

src/simulation/m_ibm.fpp

@@ -1542,21 +1542,17 @@ contains
                 @:DEALLOCATE(ib_airfoil_grids(i)%lower)
             end if
         end do
-
         if (allocated(models)) then
-            if (size(models) > 0) then
-                @:DEALLOCATE(models)
-            else
-                deallocate (models)
-            end if
+            @:DEALLOCATE(models)
+        end if
+        if (allocated(ghost_points)) then
+            @:DEALLOCATE(ghost_points)
         end if
-
         if (collision_model > 0) call s_finalize_collisions_module()
-
 #ifdef MFC_MPI
         if (num_procs > 1) then
             @:DEALLOCATE(send_ids, send_ft)
-            deallocate (recv_forces_snap, recv_torques_snap, recv_ids, recv_ft)
+            @:DEALLOCATE(recv_forces_snap, recv_torques_snap, recv_ids, recv_ft)
         end if
 #endif
 

toolchain/mfc/lint_source.py

@@ -309,6 +309,141 @@ def check_junk_comments(repo_root: Path) -> list[str]:
     return errors
 
 
+def check_allocate_deallocate_pairing(repo_root: Path) -> list[str]:
+    """Flag @:ALLOCATE'd array names with no matching @:DEALLOCATE anywhere in src/.
+
+    Every @:ALLOCATE must have a matching @:DEALLOCATE so that GPU device
+    memory is properly released alongside host memory.
+    """
+    errors: list[str] = []
+    src_dir = repo_root / SRC_DIR
+
+    # Known program-lifetime allocations with no finalize subroutine
+    PROGRAM_LIFETIME_EXEMPTIONS = {
+        # m_helper
+        "weight",
+        "pb0",
+        "Re_trans_T",
+        # m_model
+        "gpu_ntrs",
+        "gpu_trs_v",
+        "gpu_trs_n",
+        "gpu_boundary_edge_count",
+        "gpu_total_vertices",
+        "gpu_boundary_v",
+        # m_variables_conversion
+        "gs_min",
+        "pi_infs",
+        "ps_inf",
+        "cvs",
+        "qvs",
+        "qvps",
+        "Gs_vc",
+        # m_start_up post_process
+        "data_in",
+        "data_out",
+        "data_cmplx",
+        "data_cmplx_y",
+        "data_cmplx_z",
+        "En_real",
+        "En",
+        # m_acoustic_src
+        "loc_acoustic",
+        "mass_src",
+        "mom_src",
+        "E_src",
+        "source_spatials_num_points",
+        "source_spatials",
+        # m_bubbles_EE
+        "bub_adv_src",
+        "bub_r_src",
+        "bub_v_src",
+        "bub_p_src",
+        "bub_m_src",
+        "divu",
+        "ms",
+        "ps",
+        "rs",
+        "vs",
+        # m_qbmm
+        "bubmoms",
+        "momrhs",
+        # m_cbc
+        "F_src_rsx_vf",
+        "flux_src_rsx_vf_l",
+        "F_src_rsy_vf",
+        "flux_src_rsy_vf_l",
+        "F_src_rsz_vf",
+        "flux_src_rsz_vf_l",
+        "pres_in",
+        "Del_in",
+        "alpha_rho_in",
+        # m_data_output
+        "Rc_sf",
+        # m_fftw
+        "data_cmplx_gpu",
+        "data_fltr_cmplx_gpu",
+        # m_global_parameters
+        "qbmm_idx",
+        "x_cc",
+        "dx",
+        "y_cc",
+        "dy",
+        "z_cc",
+        "dz",
+        # m_hypoelastic
+        "dw_dx_hypo",
+        # m_igr
+        "coeff_R",
+        # m_rhs
+        "qR_rsx_vf",
+        "dqR_rsx_vf",
+        # m_surface_tension
+        "gR_x",
+        # m_time_steppers
+        "q_prim_ts2",
+        # m_weno
+        "poly_coef_cbR_x",
+        "d_cbR_x",
+        "poly_coef_cbR_y",
+        "d_cbR_y",
+        "poly_coef_cbR_z",
+        "d_cbR_z",
+        "divu%sf",
+        "qbmm_idx%ps",
+    }
+
+    allocate_re = re.compile(r"@:ALLOCATE\((\w[\w%]*)")
+    deallocate_re = re.compile(r"@:DEALLOCATE\((\w[\w%]*)")
+
+    # Collect all deallocated names across all files
+    deallocated: set[str] = set()
+    for src in _fortran_fpp_files(src_dir):
+        text = src.read_text(encoding="utf-8")
+        for match in deallocate_re.finditer(text):
+            deallocated.add(match.group(1))
+
+    # Check each allocation against the global deallocated set
+    for src in _fortran_fpp_files(src_dir):
+        lines = src.read_text(encoding="utf-8").splitlines()
+        rel = src.relative_to(repo_root)
+        for i, line in enumerate(lines):
+            stripped = line.strip()
+            if _is_comment_or_blank(stripped):
+                continue
+            match = allocate_re.search(stripped)
+            if match:
+                name = match.group(1)
+                if name not in deallocated and name not in PROGRAM_LIFETIME_EXEMPTIONS:
+                    errors.append(
+                        f"  {rel}:{i + 1} @:ALLOCATE({name}...) has no matching "
+                        f"@:DEALLOCATE anywhere in src/. Fix: add @:DEALLOCATE in "
+                        f"the module's s_finalize_* subroutine or annotate as program-lifetime"
+                    )
+
+    return errors
+
+
 def main():
     repo_root = Path(__file__).resolve().parents[2]
 
@@ -321,6 +456,7 @@ def main():
     all_errors.extend(check_fypp_list_duplicates(repo_root))
     all_errors.extend(check_duplicate_lines(repo_root))
     all_errors.extend(check_hardcoded_byte_size(repo_root))
+    all_errors.extend(check_allocate_deallocate_pairing(repo_root))
 
     if all_errors:
         print("Source lint failed:")