[newchem-cpp] more clang-tidy checks

.clang-format-ignore

@@ -46,6 +46,7 @@ src/clib/solve_chemistry.c
 src/clib/solve_rate_cool_g-cpp.cpp
 src/clib/status_reporting.c
 src/clib/status_reporting.h
+src/clib/step_rate_gauss_seidel.hpp
 src/clib/step_rate_newton_raphson.hpp
 src/clib/time_deriv_0d.hpp
 src/clib/update_UVbackground_rates.c

.clang-tidy

@@ -40,12 +40,15 @@ Checks: >
   cert-flp30-c,
   cert-mem57-cpp,
 
+  clang-analyzer-*,
+
   cppcoreguidelines-avoid-goto,
   cppcoreguidelines-avoid-non-const-global-variables,
   cppcoreguidelines-virtual-class-destructor
 
   google-build-using-namespace,
   google-explicit-constructor,
+  google-global-names-in-headers,
   google-readability-avoid-underscore-in-googletest-name,
   google-runtime-float,
   google-upgrade-googletest-case,

src/clib/CMakeLists.txt

@@ -123,6 +123,7 @@ add_library(Grackle_Grackle
   rate_utils.cpp
   scale_fields.cpp scale_fields.hpp
   solve_rate_cool_g-cpp.cpp solve_rate_cool_g-cpp.h
+  step_rate_gauss_seidel.hpp
   step_rate_newton_raphson.hpp
   time_deriv_0d.hpp
   utils-cpp.cpp utils-cpp.hpp

src/clib/calc_temp_cloudy_g.cpp

@@ -41,7 +41,16 @@ void calc_temp_cloudy_g(gr_float* temperature_data_, int imetal,
   const double dom = internalu_calc_dom_(internalu);
   const double zr = 1. / (internalu.a_value * internalu.a_units) - 1.;
 
-  // Convert densities from comoving to proper
+  // this assertion is a hint to clang-analyzer about the relationship between
+  // `imetal` and whether `metal_density` is a nullptr
+  // -> for context, `scale_fields_table` is inlined into this function. Rather
+  //    than look at `imetal`, it checks if `metal_density` is a nullptr
+  // -> without this assertion clang-tidy will infer that since there's an
+  //    explicit check for whether `metal_density` is null, regardless of
+  //    `imetal`'s value, then it must be possible for `metal_density` to be
+  //    null when `imetal` is 1. Then, it would report an error
+  GR_INTERNAL_REQUIRE((imetal != 1) || (my_fields->metal_density != nullptr),
+                      "imetal has an incorrect value");
 
   if (internalu.extfields_in_comoving == 1) {
     double factor = std::pow(internalu.a_value, -3);

src/clib/cool1d_multi_g.cpp

@@ -959,7 +959,6 @@ void grackle::impl::cool1d_multi_g(
         if (itmask[i] != MASK_FALSE) {
           // Only calculate if H2I(i) is a substantial fraction
           if (d(i, idx_range.j, idx_range.k) * dom > 1e10) {
-            ciefudge = 1.;
             tau = std::pow(((d(i, idx_range.j, idx_range.k) / 2e16) * dom),
                            2.8);  // 2e16 is in units of cm^-3
             tau = std::fmax(tau, 1.e-5);
@@ -1969,4 +1968,4 @@ void grackle::impl::cool1d_multi_g(
   grackle::impl::drop_GrainSpeciesCollection(&gas_grainsp_heatrate);
 
   return;
-}
+}

src/clib/fortran_func_decls.h

@@ -266,70 +266,6 @@ void FORTRAN_NAME(rate_timestep_g)(
   gr_float* kdissH2O_data_ptr
 );
 
-void FORTRAN_NAME(step_rate_g)(
-  gr_float* de_data_ptr, gr_float* HI_data_ptr, gr_float* HII_data_ptr,
-  gr_float* HeI_data_ptr, gr_float* HeII_data_ptr, gr_float* HeIII_data_ptr,
-  gr_float* d_data_ptr, gr_float* HM_data_ptr, gr_float* H2I_data_ptr,
-  gr_float* H2II_data_ptr, gr_float* DI_data_ptr, gr_float* DII_data_ptr,
-  gr_float* HDI_data_ptr, double* dtit, int* in, int* jn, int* kn, int* is,
-  int* ie, int* j, int* k, int* ispecies, gr_mask_type* anydust, double* k1,
-  double* k2, double* k3, double* k4, double* k5, double* k6, double* k7,
-  double* k8, double* k9, double* k10, double* k11, double* k12, double* k13,
-  double* k14, double* k15, double* k16, double* k17, double* k18, double* k19,
-  double* k22, double* k24, double* k25, double* k26, double* k27, double* k28,
-  double* k29, double* k30, double* k50, double* k51, double* k52, double* k53,
-  double* k54, double* k55, double* k56, double* k57, double* k58,
-  double* h2dust, double* rhoH, double* k24shield, double* k25shield,
-  double* k26shield, double* k28shield, double* k29shield, double* k30shield,
-  double* k31shield, double* HIp, double* HIIp, double* HeIp, double* HeIIp,
-  double* HeIIIp, double* dep, double* HMp, double* H2Ip, double* H2IIp,
-  double* DIp, double* DIIp, double* HDIp, double* dedot_prev,
-  double* HIdot_prev, int* iradtrans, int* irt_honly, gr_float* kphHI_data_ptr,
-  gr_float* kphHeI_data_ptr, gr_float* kphHeII_data_ptr, gr_mask_type* itmask,
-  gr_mask_type* itmask_metal, gr_float* DM_data_ptr, gr_float* HDII_data_ptr,
-  gr_float* HeHII_data_ptr, int* imetal, gr_float* metal_data_ptr, int* imchem,
-  int* idspecies, int* igrgr, int* idsub, gr_float* CI_data_ptr,
-  gr_float* CII_data_ptr, gr_float* CO_data_ptr, gr_float* CO2_data_ptr,
-  gr_float* OI_data_ptr, gr_float* OH_data_ptr, gr_float* H2O_data_ptr,
-  gr_float* O2_data_ptr, gr_float* SiI_data_ptr, gr_float* SiOI_data_ptr,
-  gr_float* SiO2I_data_ptr, gr_float* CH_data_ptr, gr_float* CH2_data_ptr,
-  gr_float* COII_data_ptr, gr_float* OII_data_ptr, gr_float* OHII_data_ptr,
-  gr_float* H2OII_data_ptr, gr_float* H3OII_data_ptr, gr_float* O2II_data_ptr,
-  gr_float* Mg_data_ptr, gr_float* Al_data_ptr, gr_float* S_data_ptr,
-  gr_float* Fe_data_ptr, gr_float* SiM_data_ptr, gr_float* FeM_data_ptr,
-  gr_float* Mg2SiO4_data_ptr, gr_float* MgSiO3_data_ptr,
-  gr_float* Fe3O4_data_ptr, gr_float* AC_data_ptr, gr_float* SiO2D_data_ptr,
-  gr_float* MgO_data_ptr, gr_float* FeS_data_ptr, gr_float* Al2O3_data_ptr,
-  gr_float* reforg_data_ptr, gr_float* volorg_data_ptr,
-  gr_float* H2Oice_data_ptr, double* k125, double* k129, double* k130,
-  double* k131, double* k132, double* k133, double* k134, double* k135,
-  double* k136, double* k137, double* k148, double* k149, double* k150,
-  double* k151, double* k152, double* k153, double* kz15, double* kz16,
-  double* kz17, double* kz18, double* kz19, double* kz20, double* kz21,
-  double* kz22, double* kz23, double* kz24, double* kz25, double* kz26,
-  double* kz27, double* kz28, double* kz29, double* kz30, double* kz31,
-  double* kz32, double* kz33, double* kz34, double* kz35, double* kz36,
-  double* kz37, double* kz38, double* kz39, double* kz40, double* kz41,
-  double* kz42, double* kz43, double* kz44, double* kz45, double* kz46,
-  double* kz47, double* kz48, double* kz49, double* kz50, double* kz51,
-  double* kz52, double* kz53, double* kz54, double* DMp, double* HDIIp,
-  double* HeHIIp, double* CIp, double* CIIp, double* COp, double* CO2p,
-  double* OIp, double* OHp, double* H2Op, double* O2p, double* SiIp,
-  double* SiOIp, double* SiO2Ip, double* CHp, double* CH2p, double* COIIp,
-  double* OIIp, double* OHIIp, double* H2OIIp, double* H3OIIp, double* O2IIp,
-  double* Mgp, double* Alp, double* Sp, double* Fep, gr_float* SiMp,
-  gr_float* FeMp, gr_float* Mg2SiO4p, gr_float* MgSiO3p, gr_float* Fe3O4p,
-  gr_float* ACp, gr_float* SiO2Dp, gr_float* MgOp, gr_float* FeSp,
-  gr_float* Al2O3p, gr_float* reforgp, gr_float* volorgp, gr_float* H2Oicep,
-  double* kdSiM, double* kdFeM, double* kdMg2SiO4, double* kdMgSiO3,
-  double* kdFe3O4, double* kdAC, double* kdSiO2D, double* kdMgO, double* kdFeS,
-  double* kdAl2O3, double* kdreforg, double* kdvolorg, double* kdH2Oice,
-  int* idissHDI, gr_float* kdissHDI_data_ptr, int* iionZ,
-  gr_float* kphCI_data_ptr, gr_float* kphOI_data_ptr, int* idissZ,
-  gr_float* kdissCO_data_ptr, gr_float* kdissOH_data_ptr,
-  gr_float* kdissH2O_data_ptr
-);
-
 void FORTRAN_NAME(make_consistent_g)(
   gr_float* de_data_ptr, gr_float* HI_data_ptr, gr_float* HII_data_ptr,
   gr_float* HeI_data_ptr, gr_float* HeII_data_ptr, gr_float* HeIII_data_ptr,

src/clib/fortran_func_wrappers.hpp

@@ -31,6 +31,8 @@
 #include "LUT.hpp"
 #include "utils-cpp.hpp"
 
+#include "step_rate_gauss_seidel.hpp"
+
 // callers of these functions are generally expected to locally shorten the
 // namespace name when they call these routines
 namespace grackle::impl::fortran_wrapper {
@@ -370,79 +372,6 @@ inline void rate_timestep_g(
                               );
 }
 
-/// Uses one linearly implicit Gauss-Seidel sweep of a backward-Euler time
-/// integrator to advance the rate equations by one (sub-)cycle (dtit).
-inline void step_rate_g(
-  double* dtit, IndexRange idx_range, gr_mask_type anydust, double* h2dust,
-  double* rhoH, double* dedot_prev, double* HIdot_prev,
-  gr_mask_type* itmask, gr_mask_type* itmask_metal, int imetal,
-  chemistry_data* my_chemistry, grackle_field_data* my_fields,
-  photo_rate_storage my_uvb_rates,
-  grackle::impl::GrainSpeciesCollection grain_growth_rates,
-  grackle::impl::SpeciesCollection species_tmpdens,
-  grackle::impl::CollisionalRxnRateCollection kcr_buf,
-  grackle::impl::PhotoRxnRateCollection kshield_buf
-) {
-           FORTRAN_NAME(step_rate_g)(my_fields->e_density, my_fields->HI_density, my_fields->HII_density, my_fields->HeI_density, my_fields->HeII_density, my_fields->HeIII_density, my_fields->density,
-                         my_fields->HM_density, my_fields->H2I_density, my_fields->H2II_density, my_fields->DI_density, my_fields->DII_density, my_fields->HDI_density, dtit,
-                         &my_fields->grid_dimension[0], &my_fields->grid_dimension[1], &my_fields->grid_dimension[2], &idx_range.i_start, &idx_range.i_end, &idx_range.jp1, &idx_range.kp1,
-                         &my_chemistry->primordial_chemistry, &anydust,
-                         kcr_buf.data[CollisionalRxnLUT::k1], kcr_buf.data[CollisionalRxnLUT::k2], kcr_buf.data[CollisionalRxnLUT::k3], kcr_buf.data[CollisionalRxnLUT::k4], kcr_buf.data[CollisionalRxnLUT::k5], kcr_buf.data[CollisionalRxnLUT::k6], kcr_buf.data[CollisionalRxnLUT::k7], kcr_buf.data[CollisionalRxnLUT::k8], kcr_buf.data[CollisionalRxnLUT::k9], kcr_buf.data[CollisionalRxnLUT::k10], kcr_buf.data[CollisionalRxnLUT::k11],
-                         kcr_buf.data[CollisionalRxnLUT::k12], kcr_buf.data[CollisionalRxnLUT::k13], kcr_buf.data[CollisionalRxnLUT::k14], kcr_buf.data[CollisionalRxnLUT::k15], kcr_buf.data[CollisionalRxnLUT::k16], kcr_buf.data[CollisionalRxnLUT::k17], kcr_buf.data[CollisionalRxnLUT::k18], kcr_buf.data[CollisionalRxnLUT::k19], kcr_buf.data[CollisionalRxnLUT::k22],
-                         &my_uvb_rates.k24, &my_uvb_rates.k25, &my_uvb_rates.k26, &my_uvb_rates.k27, &my_uvb_rates.k28, &my_uvb_rates.k29, &my_uvb_rates.k30,
-                         kcr_buf.data[CollisionalRxnLUT::k50], kcr_buf.data[CollisionalRxnLUT::k51], kcr_buf.data[CollisionalRxnLUT::k52], kcr_buf.data[CollisionalRxnLUT::k53], kcr_buf.data[CollisionalRxnLUT::k54], kcr_buf.data[CollisionalRxnLUT::k55], kcr_buf.data[CollisionalRxnLUT::k56], kcr_buf.data[CollisionalRxnLUT::k57], kcr_buf.data[CollisionalRxnLUT::k58],
-                         h2dust, rhoH,
-                         kshield_buf.k24, kshield_buf.k25, kshield_buf.k26,
-                         kshield_buf.k28, kshield_buf.k29, kshield_buf.k30, kshield_buf.k31,
-                         species_tmpdens.data[SpLUT::HI], species_tmpdens.data[SpLUT::HII], species_tmpdens.data[SpLUT::HeI], species_tmpdens.data[SpLUT::HeII], species_tmpdens.data[SpLUT::HeIII], species_tmpdens.data[SpLUT::e],
-                         species_tmpdens.data[SpLUT::HM], species_tmpdens.data[SpLUT::H2I], species_tmpdens.data[SpLUT::H2II], species_tmpdens.data[SpLUT::DI], species_tmpdens.data[SpLUT::DII], species_tmpdens.data[SpLUT::HDI],
-                         dedot_prev, HIdot_prev,
-                         &my_chemistry->use_radiative_transfer, &my_chemistry->radiative_transfer_hydrogen_only,
-                         my_fields->RT_HI_ionization_rate, my_fields->RT_HeI_ionization_rate, my_fields->RT_HeII_ionization_rate,
-                         itmask, itmask_metal,
-                        my_fields->DM_density, my_fields->HDII_density, my_fields->HeHII_density, &imetal, my_fields->metal_density,
-                        &my_chemistry->metal_chemistry, &my_chemistry->dust_species, &my_chemistry->grain_growth, &my_chemistry->dust_sublimation,
-                        my_fields->CI_density, my_fields->CII_density, my_fields->CO_density, my_fields->CO2_density,
-                        my_fields->OI_density, my_fields->OH_density, my_fields->H2O_density, my_fields->O2_density,
-                        my_fields->SiI_density, my_fields->SiOI_density, my_fields->SiO2I_density,
-                        my_fields->CH_density, my_fields->CH2_density, my_fields->COII_density, my_fields->OII_density,
-                        my_fields->OHII_density, my_fields->H2OII_density, my_fields->H3OII_density, my_fields->O2II_density,
-                        my_fields->Mg_density, my_fields->Al_density, my_fields->S_density, my_fields->Fe_density,
-                        my_fields->SiM_dust_density, my_fields->FeM_dust_density, my_fields->Mg2SiO4_dust_density, my_fields->MgSiO3_dust_density, my_fields->Fe3O4_dust_density,
-                        my_fields->AC_dust_density, my_fields->SiO2_dust_density, my_fields->MgO_dust_density, my_fields->FeS_dust_density, my_fields->Al2O3_dust_density,
-                        my_fields->ref_org_dust_density, my_fields->vol_org_dust_density, my_fields->H2O_ice_dust_density,
-                        kcr_buf.data[CollisionalRxnLUT::k125], kcr_buf.data[CollisionalRxnLUT::k129], kcr_buf.data[CollisionalRxnLUT::k130], kcr_buf.data[CollisionalRxnLUT::k131], kcr_buf.data[CollisionalRxnLUT::k132],
-                        kcr_buf.data[CollisionalRxnLUT::k133], kcr_buf.data[CollisionalRxnLUT::k134], kcr_buf.data[CollisionalRxnLUT::k135], kcr_buf.data[CollisionalRxnLUT::k136], kcr_buf.data[CollisionalRxnLUT::k137],
-                        kcr_buf.data[CollisionalRxnLUT::k148], kcr_buf.data[CollisionalRxnLUT::k149], kcr_buf.data[CollisionalRxnLUT::k150], kcr_buf.data[CollisionalRxnLUT::k151], kcr_buf.data[CollisionalRxnLUT::k152],
-                        kcr_buf.data[CollisionalRxnLUT::k153],
-                        kcr_buf.data[CollisionalRxnLUT::kz15],  kcr_buf.data[CollisionalRxnLUT::kz16],  kcr_buf.data[CollisionalRxnLUT::kz17],  kcr_buf.data[CollisionalRxnLUT::kz18],  kcr_buf.data[CollisionalRxnLUT::kz19],
-                        kcr_buf.data[CollisionalRxnLUT::kz20],  kcr_buf.data[CollisionalRxnLUT::kz21],  kcr_buf.data[CollisionalRxnLUT::kz22],  kcr_buf.data[CollisionalRxnLUT::kz23],  kcr_buf.data[CollisionalRxnLUT::kz24],
-                        kcr_buf.data[CollisionalRxnLUT::kz25],  kcr_buf.data[CollisionalRxnLUT::kz26],  kcr_buf.data[CollisionalRxnLUT::kz27],  kcr_buf.data[CollisionalRxnLUT::kz28],  kcr_buf.data[CollisionalRxnLUT::kz29],
-                        kcr_buf.data[CollisionalRxnLUT::kz30],  kcr_buf.data[CollisionalRxnLUT::kz31],  kcr_buf.data[CollisionalRxnLUT::kz32],  kcr_buf.data[CollisionalRxnLUT::kz33],  kcr_buf.data[CollisionalRxnLUT::kz34],
-                        kcr_buf.data[CollisionalRxnLUT::kz35],  kcr_buf.data[CollisionalRxnLUT::kz36],  kcr_buf.data[CollisionalRxnLUT::kz37],  kcr_buf.data[CollisionalRxnLUT::kz38],  kcr_buf.data[CollisionalRxnLUT::kz39],
-                        kcr_buf.data[CollisionalRxnLUT::kz40],  kcr_buf.data[CollisionalRxnLUT::kz41],  kcr_buf.data[CollisionalRxnLUT::kz42],  kcr_buf.data[CollisionalRxnLUT::kz43],  kcr_buf.data[CollisionalRxnLUT::kz44],
-                        kcr_buf.data[CollisionalRxnLUT::kz45],  kcr_buf.data[CollisionalRxnLUT::kz46],  kcr_buf.data[CollisionalRxnLUT::kz47],  kcr_buf.data[CollisionalRxnLUT::kz48],  kcr_buf.data[CollisionalRxnLUT::kz49],
-                        kcr_buf.data[CollisionalRxnLUT::kz50],  kcr_buf.data[CollisionalRxnLUT::kz51],  kcr_buf.data[CollisionalRxnLUT::kz52],  kcr_buf.data[CollisionalRxnLUT::kz53],  kcr_buf.data[CollisionalRxnLUT::kz54],
-                        species_tmpdens.data[SpLUT::DM], species_tmpdens.data[SpLUT::HDII], species_tmpdens.data[SpLUT::HeHII],
-                        species_tmpdens.data[SpLUT::CI], species_tmpdens.data[SpLUT::CII], species_tmpdens.data[SpLUT::CO], species_tmpdens.data[SpLUT::CO2],
-                        species_tmpdens.data[SpLUT::OI], species_tmpdens.data[SpLUT::OH], species_tmpdens.data[SpLUT::H2O], species_tmpdens.data[SpLUT::O2],
-                        species_tmpdens.data[SpLUT::SiI], species_tmpdens.data[SpLUT::SiOI], species_tmpdens.data[SpLUT::SiO2I],
-                        species_tmpdens.data[SpLUT::CH], species_tmpdens.data[SpLUT::CH2], species_tmpdens.data[SpLUT::COII], species_tmpdens.data[SpLUT::OII],
-                        species_tmpdens.data[SpLUT::OHII], species_tmpdens.data[SpLUT::H2OII], species_tmpdens.data[SpLUT::H3OII], species_tmpdens.data[SpLUT::O2II],
-                        species_tmpdens.data[SpLUT::Mg], species_tmpdens.data[SpLUT::Al], species_tmpdens.data[SpLUT::S], species_tmpdens.data[SpLUT::Fe],
-                        species_tmpdens.data[SpLUT::SiM_dust], species_tmpdens.data[SpLUT::FeM_dust], species_tmpdens.data[SpLUT::Mg2SiO4_dust], species_tmpdens.data[SpLUT::MgSiO3_dust], species_tmpdens.data[SpLUT::Fe3O4_dust],
-                        species_tmpdens.data[SpLUT::AC_dust], species_tmpdens.data[SpLUT::SiO2_dust], species_tmpdens.data[SpLUT::MgO_dust], species_tmpdens.data[SpLUT::FeS_dust], species_tmpdens.data[SpLUT::Al2O3_dust],
-                        species_tmpdens.data[SpLUT::ref_org_dust], species_tmpdens.data[SpLUT::vol_org_dust], species_tmpdens.data[SpLUT::H2O_ice_dust],
-                        grain_growth_rates.data[OnlyGrainSpLUT::SiM_dust], grain_growth_rates.data[OnlyGrainSpLUT::FeM_dust], grain_growth_rates.data[OnlyGrainSpLUT::Mg2SiO4_dust], grain_growth_rates.data[OnlyGrainSpLUT::MgSiO3_dust], grain_growth_rates.data[OnlyGrainSpLUT::Fe3O4_dust],
-                        grain_growth_rates.data[OnlyGrainSpLUT::AC_dust], grain_growth_rates.data[OnlyGrainSpLUT::SiO2_dust], grain_growth_rates.data[OnlyGrainSpLUT::MgO_dust], grain_growth_rates.data[OnlyGrainSpLUT::FeS_dust], grain_growth_rates.data[OnlyGrainSpLUT::Al2O3_dust],
-                        grain_growth_rates.data[OnlyGrainSpLUT::ref_org_dust], grain_growth_rates.data[OnlyGrainSpLUT::vol_org_dust], grain_growth_rates.data[OnlyGrainSpLUT::H2O_ice_dust],
-                        &my_chemistry->radiative_transfer_HDI_dissociation, my_fields->RT_HDI_dissociation_rate, &my_chemistry->radiative_transfer_metal_ionization, my_fields->RT_CI_ionization_rate, my_fields->RT_OI_ionization_rate,
-                        &my_chemistry->radiative_transfer_metal_dissociation, my_fields->RT_CO_dissociation_rate, my_fields->RT_OH_dissociation_rate, my_fields->RT_H2O_dissociation_rate
-               );
-
-}
-
-
 } // namespace grackle::impl::fortran_wrapper
 
 #endif /* FORTRAN_FUNC_WRAPPERS_HPP */

src/clib/initialize_chemistry_data.cpp

@@ -463,16 +463,34 @@ extern "C" int local_initialize_chemistry_data(chemistry_data *my_chemistry,
     tm_info = localtime(&timer);
     strftime(tstr, 26, "%Y-%m-%d %H:%M:%S", tm_info);
 
-    FILE *fptr = fopen("GRACKLE_INFO", "w");
-    fprintf(fptr, "%s\n", tstr);
-    show_version(fptr);
-    fprintf(fptr, "Grackle build options:\n");
-    auto_show_config(fptr);
-    fprintf(fptr, "Grackle build flags:\n");
-    auto_show_flags(fptr);
-    fprintf(fptr, "Grackle run-time parameters:\n");
-    show_parameters(fptr, my_chemistry);
-    fclose(fptr);
+    const char* fname = "GRACKLE_INFO";
+
+    FILE *fptr = fopen(fname, "w");
+    if (fptr == nullptr) {
+      // on posix platforms we could give a more detailed error message
+      // - posix (not the C or C++ standard) mandates that `fopen` set errno
+      //   upon failure
+      // - properly informing the user of the error gets a little "hairy." We
+      //   should use POSIX's strerror_r to get the error (since regular
+      //   strerror may not be threadsafe). But we would need to account for
+      //   the fact that glibc describes an incompatible signature for
+      //   strerror_r (https://www.club.cc.cmu.edu/~cmccabe/blog_strerror.html)
+      // Since this isn't central to Grackle's functionality, we'll punt on
+      // this...
+      fprintf(stderr, "Failed to open \"%s\" file (to record config info)\n",
+              fname);
+      // an argument could be made that we should return with an error
+    } else {
+      fprintf(fptr, "%s\n", tstr);
+      show_version(fptr);
+      fprintf(fptr, "Grackle build options:\n");
+      auto_show_config(fptr);
+      fprintf(fptr, "Grackle build flags:\n");
+      auto_show_flags(fptr);
+      fprintf(fptr, "Grackle run-time parameters:\n");
+      show_parameters(fptr, my_chemistry);
+      fclose(fptr);
+    }
 
     fprintf(stdout, "Grackle run-time parameters:\n");
     show_parameters(stdout, my_chemistry);