Fix CCE VLA ICE in m_chemistry.fpp + restore Python 3.9 support

Extend AMD-only VLA guards to also cover CCE 19.0.0 in all four
locations in m_chemistry.fpp:
- s_compute_q_T_sf: add USING_CCE guard for Ys array
- s_compute_T_from_primitives: add USING_CCE guard for Ys array
- s_compute_chemistry_reaction_flux: extend AMD guard to include CCE
- s_compute_chemistry_diffusion_flux: extend AMD guard to include CCE

CCE 19.0.0 LLVM InstCombine (foldIntegerTypedPHI) crashes on VLAs
(dimension(num_species)) when num_species is not a compile-time
constant (e.g., case-optimized pre_process for non-chemistry cases).
Fixed by using dimension(10) when USING_CCE.

Also restore MFC_PYTHON_MIN_MINOR=9 in python.sh (was accidentally
set to 10 in 3d8cf31; PR #1287 merged to master adds Python 3.9 support).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: Spencer Bryngelson

src/common/m_chemistry.fpp

@@ -63,7 +63,11 @@ contains
 
         integer :: x, y, z, eqn
         real(wp) :: energy, T_in
-        real(wp), dimension(num_species) :: Ys
+        #:if USING_CCE
+            real(wp), dimension(10) :: Ys
+        #:else
+            real(wp), dimension(num_species) :: Ys
+        #:endif
 
         do z = bounds(3)%beg, bounds(3)%end
             do y = bounds(2)%beg, bounds(2)%end
@@ -101,7 +105,11 @@ contains
         type(int_bounds_info), dimension(1:3), intent(in) :: bounds
 
         integer :: x, y, z, i
-        real(wp), dimension(num_species) :: Ys
+        #:if USING_CCE
+            real(wp), dimension(10) :: Ys
+        #:else
+            real(wp), dimension(num_species) :: Ys
+        #:endif
         real(wp) :: mix_mol_weight
 
         do z = bounds(3)%beg, bounds(3)%end
@@ -131,7 +139,7 @@ contains
         integer :: eqn
         real(wp) :: T
         real(wp) :: rho, omega_m
-        #:if not MFC_CASE_OPTIMIZATION and USING_AMD
+        #:if (not MFC_CASE_OPTIMIZATION and USING_AMD) or USING_CCE
             real(wp), dimension(10) :: Ys
             real(wp), dimension(10) :: omega
         #:else
@@ -180,7 +188,7 @@ contains
         type(int_bounds_info), intent(in) :: irx, iry, irz
 
         integer, intent(in) :: idir
-        #:if not MFC_CASE_OPTIMIZATION and USING_AMD
+        #:if (not MFC_CASE_OPTIMIZATION and USING_AMD) or USING_CCE
             real(wp), dimension(10) :: Xs_L, Xs_R, Xs_cell, Ys_L, Ys_R, Ys_cell
             real(wp), dimension(10) :: mass_diffusivities_mixavg1, mass_diffusivities_mixavg2
             real(wp), dimension(10) :: mass_diffusivities_mixavg_Cell, dXk_dxi, h_l, h_r, h_k

toolchain/bootstrap/python.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 
 MFC_PYTHON_MIN_MAJOR=3
-MFC_PYTHON_MIN_MINOR=10
+MFC_PYTHON_MIN_MINOR=9
 MFC_PYTHON_MIN_STR="$MFC_PYTHON_MIN_MAJOR.$MFC_PYTHON_MIN_MINOR"
 
 is_python_compatible() {