diff --git a/ortools/glop/BUILD.bazel b/ortools/glop/BUILD.bazel
index 053a27d79a..f97d27785f 100644
--- a/ortools/glop/BUILD.bazel
+++ b/ortools/glop/BUILD.bazel
@@ -225,6 +225,10 @@ cc_library(
         "//ortools/lp_data:base",
         "//ortools/lp_data:lp_utils",
         "//ortools/lp_data:sparse",
+        "//ortools/lp_data:sparse_column",
+        "@abseil-cpp//absl/base:core_headers",
+        "@abseil-cpp//absl/log",
+        "@abseil-cpp//absl/log:check",
     ],
 )
 
diff --git a/ortools/glop/initial_basis.cc b/ortools/glop/initial_basis.cc
index 97734b10e6..c2d528e317 100644
--- a/ortools/glop/initial_basis.cc
+++ b/ortools/glop/initial_basis.cc
@@ -20,8 +20,14 @@
 #include <queue>
 #include <vector>
 
+#include "absl/base/optimization.h"
+#include "absl/log/check.h"
+#include "absl/log/log.h"
 #include "ortools/glop/markowitz.h"
+#include "ortools/lp_data/lp_types.h"
 #include "ortools/lp_data/lp_utils.h"
+#include "ortools/lp_data/sparse.h"
+#include "ortools/lp_data/sparse_column.h"
 
 namespace operations_research {
 namespace glop {
@@ -219,6 +225,8 @@ int InitialBasis::GetMarosPriority(ColIndex col) const {
     case VariableType::FIXED_VARIABLE:
       return 0;
   }
+  LOG(FATAL) << "Invalid variable type: "
+             << static_cast<int>(variable_type_[col]);
 }
 
 int InitialBasis::GetMarosPriority(RowIndex row) const {
@@ -388,6 +396,7 @@ int InitialBasis::GetColumnCategory(ColIndex col) const {
     case VariableType::FIXED_VARIABLE:
       return 5;
   }
+  ABSL_UNREACHABLE();
 }
 
 Fractional InitialBasis::GetColumnPenalty(ColIndex col) const {
diff --git a/ortools/glop/primal_edge_norms.cc b/ortools/glop/primal_edge_norms.cc
index 5a39d73899..49603eb133 100644
--- a/ortools/glop/primal_edge_norms.cc
+++ b/ortools/glop/primal_edge_norms.cc
@@ -14,6 +14,7 @@
 #include "ortools/glop/primal_edge_norms.h"
 
 #include <algorithm>
+#include <cmath>
 #include <cstdlib>
 
 #include "absl/log/check.h"
@@ -68,6 +69,7 @@ DenseRow::ConstView PrimalEdgeNorms::GetSquaredNorms() {
     case GlopParameters::DEVEX:
       return GetDevexWeights().const_view();
   }
+  LOG(FATAL) << "Invalid pricing rule: " << pricing_rule_;
 }
 
 const DenseRow& PrimalEdgeNorms::GetEdgeSquaredNorms() {
diff --git a/ortools/math_opt/core/math_opt_proto_utils.cc b/ortools/math_opt/core/math_opt_proto_utils.cc
index 88392dfc34..463aa026b2 100644
--- a/ortools/math_opt/core/math_opt_proto_utils.cc
+++ b/ortools/math_opt/core/math_opt_proto_utils.cc
@@ -21,6 +21,7 @@
 #include <optional>
 #include <string>
 
+#include "absl/base/optimization.h"
 #include "absl/container/flat_hash_set.h"
 #include "absl/log/check.h"
 #include "absl/log/log.h"
@@ -403,6 +404,7 @@ absl::Status ModelIsSupported(const ModelProto& model,
       case SupportType::kSupported:
         LOG(FATAL) << "Unexpected call with `kSupported`";
     }
+    ABSL_UNREACHABLE();
   };
   if (const SupportType support = support_menu.integer_variables;
       support != SupportType::kSupported) {
diff --git a/ortools/math_opt/elemental/BUILD.bazel b/ortools/math_opt/elemental/BUILD.bazel
index 9781f2b6e3..e75df52c74 100644
--- a/ortools/math_opt/elemental/BUILD.bazel
+++ b/ortools/math_opt/elemental/BUILD.bazel
@@ -410,6 +410,7 @@ cc_test(
         ":tagged_id",
         "//ortools/base:gmock_main",
         "//ortools/math_opt/testing:stream",
+        "@abseil-cpp//absl/base:core_headers",
         "@abseil-cpp//absl/hash:hash_testing",
         "@abseil-cpp//absl/strings",
     ],
diff --git a/ortools/math_opt/elemental/tagged_id_test.cc b/ortools/math_opt/elemental/tagged_id_test.cc
index 49fc1f3435..faefea5c6d 100644
--- a/ortools/math_opt/elemental/tagged_id_test.cc
+++ b/ortools/math_opt/elemental/tagged_id_test.cc
@@ -18,6 +18,7 @@
 #include <ostream>
 #include <utility>
 
+#include "absl/base/optimization.h"
 #include "absl/hash/hash_testing.h"
 #include "absl/strings/str_cat.h"
 #include "gtest/gtest.h"
@@ -39,6 +40,7 @@ std::ostream& operator<<(std::ostream& ostr, const TestEnum& e) {
       ostr << "kValue0";
       return ostr;
   }
+  ABSL_UNREACHABLE();
 }
 
 using TestEnumId = TaggedId<TestEnum::kValue0>;
diff --git a/ortools/math_opt/solver_tests/BUILD.bazel b/ortools/math_opt/solver_tests/BUILD.bazel
index 9f31d474e6..f769aff01d 100644
--- a/ortools/math_opt/solver_tests/BUILD.bazel
+++ b/ortools/math_opt/solver_tests/BUILD.bazel
@@ -322,6 +322,7 @@ cc_library(
         "//ortools/math_opt/cpp:math_opt",
         "//ortools/math_opt/io:mps_converter",
         "//ortools/port:proto_utils",
+        "@abseil-cpp//absl/base:core_headers",
         "@abseil-cpp//absl/status",
         "@abseil-cpp//absl/status:statusor",
         "@abseil-cpp//absl/strings:string_view",
diff --git a/ortools/math_opt/solver_tests/multi_objective_tests.cc b/ortools/math_opt/solver_tests/multi_objective_tests.cc
index 098d3717b0..2ebefb11c4 100644
--- a/ortools/math_opt/solver_tests/multi_objective_tests.cc
+++ b/ortools/math_opt/solver_tests/multi_objective_tests.cc
@@ -17,6 +17,7 @@
 #include <ostream>
 #include <utility>
 
+#include "absl/base/optimization.h"
 #include "absl/status/status.h"
 #include "absl/status/statusor.h"
 #include "absl/strings/string_view.h"
@@ -210,6 +211,7 @@ absl::StatusOr<SimpleMultiObjectiveSolveResult> SolveWithObjectiveDegradation(
       case ObjectiveType::kAuxiliary:
         return model.AddMaximizationObjective(x, /*priority=*/0);
     }
+    ABSL_UNREACHABLE();
   }();
   const Objective priority_1 = [&]() {
     switch (priority_1_type) {
@@ -220,6 +222,7 @@ absl::StatusOr<SimpleMultiObjectiveSolveResult> SolveWithObjectiveDegradation(
       case ObjectiveType::kAuxiliary:
         return model.AddMinimizationObjective(x, /*priority=*/1);
     }
+    ABSL_UNREACHABLE();
   }();
   ModelSolveParameters model_parameters;
   switch (tolerance_type) {
diff --git a/ortools/math_opt/solvers/gscip/BUILD.bazel b/ortools/math_opt/solvers/gscip/BUILD.bazel
index 01474cd389..088812049a 100644
--- a/ortools/math_opt/solvers/gscip/BUILD.bazel
+++ b/ortools/math_opt/solvers/gscip/BUILD.bazel
@@ -97,6 +97,7 @@ cc_library(
         "@abseil-cpp//absl/cleanup",
         "@abseil-cpp//absl/container:flat_hash_map",
         "@abseil-cpp//absl/container:flat_hash_set",
+        "@abseil-cpp//absl/log",
         "@abseil-cpp//absl/log:check",
         "@abseil-cpp//absl/memory",
         "@abseil-cpp//absl/status",
@@ -215,6 +216,7 @@ cc_library(
     deps = [
         "//ortools/base:logging",
         "//ortools/linear_solver:scip_helper_macros",
+        "@abseil-cpp//absl/log:die_if_null",
         "@abseil-cpp//absl/status:statusor",
         "@abseil-cpp//absl/strings",
         "@scip",
@@ -225,7 +227,10 @@ cc_library(
     name = "gscip_callback_result",
     srcs = ["gscip_callback_result.cc"],
     hdrs = ["gscip_callback_result.h"],
-    deps = ["@scip"],
+    deps = [
+        "@abseil-cpp//absl/base:core_headers",
+        "@scip",
+    ],
 )
 
 cc_library(
diff --git a/ortools/math_opt/solvers/gscip/gscip.cc b/ortools/math_opt/solvers/gscip/gscip.cc
index 7bcac209d5..1b52f6cc68 100644
--- a/ortools/math_opt/solvers/gscip/gscip.cc
+++ b/ortools/math_opt/solvers/gscip/gscip.cc
@@ -22,10 +22,12 @@
 #include <utility>
 #include <vector>
 
+#include "absl/base/optimization.h"
 #include "absl/cleanup/cleanup.h"
 #include "absl/container/flat_hash_map.h"
 #include "absl/container/flat_hash_set.h"
 #include "absl/log/check.h"
+#include "absl/log/log.h"
 #include "absl/memory/memory.h"
 #include "absl/status/status.h"
 #include "absl/status/statusor.h"
@@ -35,14 +37,6 @@
 #include "absl/synchronization/mutex.h"
 #include "absl/types/span.h"
 #include "lpi/lpi.h"
-#include "ortools/base/logging.h"
-#include "ortools/base/status_macros.h"
-#include "ortools/linear_solver/scip_helper_macros.h"
-#include "ortools/math_opt/solvers/gscip/gscip.pb.h"
-#include "ortools/math_opt/solvers/gscip/gscip_event_handler.h"
-#include "ortools/math_opt/solvers/gscip/gscip_parameters.h"
-#include "ortools/port/proto_utils.h"
-#include "ortools/util/status_macros.h"
 #include "scip/cons_and.h"
 #include "scip/cons_indicator.h"
 #include "scip/cons_linear.h"
@@ -53,6 +47,13 @@
 #else
 #include "scip/cons_quadratic.h"
 #endif  // SCIP_VERSION_MAJOR >= 10
+#include "ortools/base/status_macros.h"
+#include "ortools/linear_solver/scip_helper_macros.h"
+#include "ortools/math_opt/solvers/gscip/gscip.pb.h"
+#include "ortools/math_opt/solvers/gscip/gscip_event_handler.h"
+#include "ortools/math_opt/solvers/gscip/gscip_parameters.h"
+#include "ortools/port/proto_utils.h"
+#include "ortools/util/status_macros.h"
 #include "scip/cons_sos1.h"
 #include "scip/cons_sos2.h"
 #include "scip/def.h"
@@ -102,6 +103,7 @@ SCIP_VARTYPE ConvertVarType(const GScipVarType var_type) {
     case GScipVarType::kInteger:
       return SCIP_VARTYPE_INTEGER;
   }
+  ABSL_UNREACHABLE();
 }
 
 GScipVarType ConvertVarType(const SCIP_VARTYPE var_type) {
@@ -115,6 +117,7 @@ GScipVarType ConvertVarType(const SCIP_VARTYPE var_type) {
     case SCIP_VARTYPE_BINARY:
       return GScipVarType::kBinary;
   }
+  LOG(FATAL) << "Unrecognized SCIP_VARTYPE: " << var_type;
 }
 
 GScipOutput::Status ConvertStatus(const SCIP_STATUS scip_status) {
diff --git a/ortools/math_opt/solvers/gscip/gscip_callback_result.cc b/ortools/math_opt/solvers/gscip/gscip_callback_result.cc
index 5d6b4ba71c..c4d1da265a 100644
--- a/ortools/math_opt/solvers/gscip/gscip_callback_result.cc
+++ b/ortools/math_opt/solvers/gscip/gscip_callback_result.cc
@@ -13,6 +13,7 @@
 
 #include "ortools/math_opt/solvers/gscip/gscip_callback_result.h"
 
+#include "absl/base/optimization.h"
 #include "scip/type_result.h"
 
 namespace operations_research {
@@ -56,6 +57,7 @@ SCIP_RESULT ConvertGScipCallbackResult(const GScipCallbackResult result) {
     case GScipCallbackResult::kDelayNode:
       return SCIP_DELAYNODE;
   }
+  ABSL_UNREACHABLE();
 }
 
 }  // namespace operations_research
diff --git a/ortools/math_opt/tools/BUILD.bazel b/ortools/math_opt/tools/BUILD.bazel
index d9e61c8b67..58d9f1b1e0 100644
--- a/ortools/math_opt/tools/BUILD.bazel
+++ b/ortools/math_opt/tools/BUILD.bazel
@@ -41,6 +41,7 @@ cc_binary(
         "//ortools/util:sigint",
         "//ortools/util:status_macros",
         "@abseil-cpp//absl/base:no_destructor",
+        "@abseil-cpp//absl/base:nullability",
         "@abseil-cpp//absl/flags:flag",
         "@abseil-cpp//absl/log:check",
         "@abseil-cpp//absl/status",
@@ -81,6 +82,7 @@ cc_library(
         "//ortools/math_opt/io:mps_converter",
         "//ortools/math_opt/io:proto_converter",
         "@abseil-cpp//absl/algorithm:container",
+        "@abseil-cpp//absl/base:core_headers",
         "@abseil-cpp//absl/container:flat_hash_map",
         "@abseil-cpp//absl/log",
         "@abseil-cpp//absl/status",
diff --git a/ortools/math_opt/tools/file_format_flags.cc b/ortools/math_opt/tools/file_format_flags.cc
index 01e11c1722..bf57e67fb7 100644
--- a/ortools/math_opt/tools/file_format_flags.cc
+++ b/ortools/math_opt/tools/file_format_flags.cc
@@ -20,6 +20,7 @@
 #include <vector>
 
 #include "absl/algorithm/container.h"
+#include "absl/base/optimization.h"
 #include "absl/container/flat_hash_map.h"
 #include "absl/log/log.h"
 #include "absl/status/status.h"
@@ -69,6 +70,7 @@ std::string AbslUnparseFlag(const FileFormat f) {
     case FileFormat::kLP:
       return "lp";
   }
+  ABSL_UNREACHABLE();
 }
 
 std::ostream& operator<<(std::ostream& out, const FileFormat f) {
@@ -232,6 +234,7 @@ ReadModel(const absl::string_view file_path, const FileFormat format) {
       return std::make_pair(std::move(model), std::nullopt);
     }
   }
+  ABSL_UNREACHABLE();
 }
 
 absl::Status WriteModel(const absl::string_view file_path,
@@ -267,6 +270,7 @@ absl::Status WriteModel(const absl::string_view file_path,
       return file::SetContents(file_path, lp_data, file::Defaults());
     }
   }
+  ABSL_UNREACHABLE();
 }
 
 }  // namespace operations_research::math_opt
diff --git a/ortools/pdlp/BUILD.bazel b/ortools/pdlp/BUILD.bazel
index 0e76eccfbb..64d668b803 100644
--- a/ortools/pdlp/BUILD.bazel
+++ b/ortools/pdlp/BUILD.bazel
@@ -135,6 +135,7 @@ cc_library(
         "//ortools/lp_data:proto_utils",
         "//ortools/util:logging",
         "@abseil-cpp//absl/algorithm:container",
+        "@abseil-cpp//absl/base:core_headers",
         "@abseil-cpp//absl/base:nullability",
         "@abseil-cpp//absl/log",
         "@abseil-cpp//absl/log:check",
diff --git a/ortools/pdlp/primal_dual_hybrid_gradient.cc b/ortools/pdlp/primal_dual_hybrid_gradient.cc
index b86f3e9f1c..415a145598 100644
--- a/ortools/pdlp/primal_dual_hybrid_gradient.cc
+++ b/ortools/pdlp/primal_dual_hybrid_gradient.cc
@@ -54,6 +54,7 @@
 #include "Eigen/SparseCore"
 #include "absl/algorithm/container.h"
 #include "absl/base/nullability.h"
+#include "absl/base/optimization.h"
 #include "absl/log/check.h"
 #include "absl/log/log.h"
 #include "absl/status/status.h"
@@ -250,6 +251,7 @@ void LogIterationStats(int verbosity_level, bool use_feasibility_polishing,
         case IterationType::kPresolveTermination:
           return "t ";
       }
+      ABSL_UNREACHABLE();
     } else {
       return "";
     }
diff --git a/ortools/routing/BUILD.bazel b/ortools/routing/BUILD.bazel
index 1e67a04d6c..76d07855dc 100644
--- a/ortools/routing/BUILD.bazel
+++ b/ortools/routing/BUILD.bazel
@@ -153,6 +153,7 @@ cc_library(
     deps = [
         ":enums_cc_proto",
         ":ils_cc_proto",
+        "@abseil-cpp//absl/base:core_headers",
     ],
 )
 
diff --git a/ortools/routing/ils_parameters_utils.cc b/ortools/routing/ils_parameters_utils.cc
index c4cff4b384..ddf5ed0ad2 100644
--- a/ortools/routing/ils_parameters_utils.cc
+++ b/ortools/routing/ils_parameters_utils.cc
@@ -16,6 +16,7 @@
 #include <string>
 #include <vector>
 
+#include "absl/base/optimization.h"
 #include "ortools/routing/enums.pb.h"
 #include "ortools/routing/ils.pb.h"
 
@@ -60,6 +61,7 @@ std::string GetRecreateParametersName(
     case RecreateParameters::PARAMETERS_NOT_SET:
       return "PARAMETERS_NOT_SET";
   }
+  ABSL_UNREACHABLE();
 }
 
 }  // namespace operations_research::routing
diff --git a/ortools/routing/parsers/BUILD.bazel b/ortools/routing/parsers/BUILD.bazel
index 022f7e1f6d..8674700e65 100644
--- a/ortools/routing/parsers/BUILD.bazel
+++ b/ortools/routing/parsers/BUILD.bazel
@@ -310,7 +310,9 @@ cc_library(
     deps = [
         ":simple_graph",
         "//ortools/base:file",
-        "//ortools/base:logging",
+        "@abseil-cpp//absl/base:core_headers",
+        "@abseil-cpp//absl/log",
+        "@abseil-cpp//absl/log:check",
         "@abseil-cpp//absl/strings",
         "@abseil-cpp//absl/strings:str_format",
         "@abseil-cpp//absl/time",
diff --git a/ortools/routing/parsers/solution_serializer.cc b/ortools/routing/parsers/solution_serializer.cc
index a92efccbff..a28c567401 100644
--- a/ortools/routing/parsers/solution_serializer.cc
+++ b/ortools/routing/parsers/solution_serializer.cc
@@ -14,16 +14,25 @@
 #include "ortools/routing/parsers/solution_serializer.h"
 
 #include <algorithm>
+#include <cstdint>
 #include <optional>
 #include <string>
 #include <string_view>
 #include <vector>
 
+#include "absl/base/attributes.h"
+#include "absl/log/check.h"
+#include "absl/log/log.h"
 #include "absl/strings/ascii.h"
+#include "absl/strings/str_cat.h"
+#include "absl/strings/str_format.h"
 #include "absl/time/clock.h"
 #include "absl/time/time.h"
 #include "absl/types/span.h"
-#include "ortools/base/logging.h"
+#include "ortools/base/file.h"
+#include "ortools/base/helpers.h"
+#include "ortools/base/options.h"
+#include "ortools/routing/parsers/simple_graph.h"
 
 namespace operations_research::routing {
 
diff --git a/ortools/routing/parsers/solution_serializer.h b/ortools/routing/parsers/solution_serializer.h
index d1f545cafa..4e3996579a 100644
--- a/ortools/routing/parsers/solution_serializer.h
+++ b/ortools/routing/parsers/solution_serializer.h
@@ -17,19 +17,20 @@
 #ifndef ORTOOLS_ROUTING_PARSERS_SOLUTION_SERIALIZER_H_
 #define ORTOOLS_ROUTING_PARSERS_SOLUTION_SERIALIZER_H_
 
+#include <cstdint>
 #include <optional>
 #include <string>
 #include <string_view>
 #include <utility>
 #include <vector>
 
+#include "absl/base/attributes.h"
+#include "absl/base/optimization.h"
+#include "absl/log/check.h"
 #include "absl/strings/str_cat.h"
 #include "absl/strings/str_format.h"
 #include "absl/strings/string_view.h"
 #include "absl/types/span.h"
-#include "ortools/base/file.h"
-#include "ortools/base/helpers.h"
-#include "ortools/base/logging.h"
 #include "ortools/routing/parsers/simple_graph.h"
 
 namespace operations_research::routing {
@@ -162,6 +163,7 @@ class RoutingSolution {
       case RoutingOutputFormat::kNEARPLIB:
         return SerializeToNEARPLIBString();
     }
+    ABSL_UNREACHABLE();
   }
 
   // Serializes the full solution to the given file, including metadata like
@@ -180,6 +182,7 @@ class RoutingSolution {
       case RoutingOutputFormat::kNEARPLIB:
         return SerializeToNEARPLIBSolutionFile();
     }
+    ABSL_UNREACHABLE();
   }
 
   // Serializes the full solution to the given file, including metadata like
@@ -263,6 +266,7 @@ std::string FormatStatistic(absl::string_view name, T value,
     case RoutingOutputFormat::kNEARPLIB:
       return absl::StrCat(name, " : ", value);
   }
+  ABSL_UNREACHABLE();
 }
 
 // Specialization for doubles to show a higher precision: without this
@@ -282,6 +286,7 @@ inline std::string FormatStatistic(absl::string_view name, double value,
     case RoutingOutputFormat::kNEARPLIB:
       return absl::StrFormat("%s : %f", name, value);
   }
+  ABSL_UNREACHABLE();
 }
 
 // Prints a formatted solution or solver statistic according to the given
diff --git a/ortools/sat/2d_rectangle_presolve.cc b/ortools/sat/2d_rectangle_presolve.cc
index a3edee8627..152e48191f 100644
--- a/ortools/sat/2d_rectangle_presolve.cc
+++ b/ortools/sat/2d_rectangle_presolve.cc
@@ -318,6 +318,7 @@ struct Edge {
                 .y_start = rectangle.y_min,
                 .size = rectangle.SizeY()};
     }
+    LOG(FATAL) << "Invalid edge position: " << static_cast<int>(pos);
   }
 
   template <typename H>
@@ -598,6 +599,7 @@ IntegerValue GetClockwiseStart(EdgePosition edge, const Rectangle& rectangle) {
     case EdgePosition::TOP:
       return rectangle.x_min;
   }
+  LOG(FATAL) << "Invalid edge position: " << static_cast<int>(edge);
 }
 
 IntegerValue GetClockwiseEnd(EdgePosition edge, const Rectangle& rectangle) {
@@ -611,6 +613,7 @@ IntegerValue GetClockwiseEnd(EdgePosition edge, const Rectangle& rectangle) {
     case EdgePosition::TOP:
       return rectangle.x_max;
   }
+  LOG(FATAL) << "Invalid edge position: " << static_cast<int>(edge);
 }
 
 // Given a list of rectangles and their neighbours graph, find the list of
diff --git a/ortools/sat/2d_rectangle_presolve.h b/ortools/sat/2d_rectangle_presolve.h
index 1ed1295fa2..19a4cbe666 100644
--- a/ortools/sat/2d_rectangle_presolve.h
+++ b/ortools/sat/2d_rectangle_presolve.h
@@ -21,6 +21,7 @@
 #include "absl/algorithm/container.h"
 #include "absl/container/flat_hash_map.h"
 #include "absl/container/inlined_vector.h"
+#include "absl/log/log.h"
 #include "absl/types/span.h"
 #include "ortools/sat/diffn_util.h"
 #include "ortools/sat/integer_base.h"
@@ -180,6 +181,7 @@ class Neighbours {
         case EdgePosition::RIGHT:
           return std::tie(a.y_min, a.y_max) > std::tie(b.y_min, b.y_max);
       }
+      LOG(FATAL) << "Invalid edge position: " << static_cast<int>(edge_);
     }
     EdgePosition edge_;
   };
diff --git a/ortools/sat/BUILD.bazel b/ortools/sat/BUILD.bazel
index 0820d99794..46c06284b6 100644
--- a/ortools/sat/BUILD.bazel
+++ b/ortools/sat/BUILD.bazel
@@ -426,6 +426,7 @@ cc_library(
         "//ortools/util:bitset",
         "//ortools/util:saturated_arithmetic",
         "//ortools/util:sorted_interval_list",
+        "@abseil-cpp//absl/base:core_headers",
         "@abseil-cpp//absl/container:flat_hash_map",
         "@abseil-cpp//absl/container:flat_hash_set",
         "@abseil-cpp//absl/flags:flag",
@@ -2308,6 +2309,7 @@ cc_library(
         ":sat_base",
         ":scheduling_helpers",
         ":util",
+        "@abseil-cpp//absl/base:core_headers",
         "@abseil-cpp//absl/base:log_severity",
         "@abseil-cpp//absl/log",
         "@abseil-cpp//absl/log:check",
@@ -3684,14 +3686,12 @@ cc_library(
         ":integer_base",
         ":scheduling_helpers",
         ":util",
-        "//ortools/base:logging",
         "//ortools/base:stl_util",
         "//ortools/base:strong_vector",
         "//ortools/graph:connected_components",
         "//ortools/graph:strongly_connected_components",
         "//ortools/util:fixed_shape_binary_tree",
         "//ortools/util:integer_pq",
-        "//ortools/util:saturated_arithmetic",
         "//ortools/util:strong_integers",
         "@abseil-cpp//absl/algorithm:container",
         "@abseil-cpp//absl/container:btree",
@@ -3703,7 +3703,6 @@ cc_library(
         "@abseil-cpp//absl/log:vlog_is_on",
         "@abseil-cpp//absl/random:bit_gen_ref",
         "@abseil-cpp//absl/strings:str_format",
-        "@abseil-cpp//absl/types:optional",
         "@abseil-cpp//absl/types:span",
     ],
 )
diff --git a/ortools/sat/cp_model_utils.cc b/ortools/sat/cp_model_utils.cc
index 678cc67781..1d925ea1c2 100644
--- a/ortools/sat/cp_model_utils.cc
+++ b/ortools/sat/cp_model_utils.cc
@@ -22,6 +22,7 @@
 #include <utility>
 #include <vector>
 
+#include "absl/base/optimization.h"
 #include "absl/container/flat_hash_map.h"
 #include "absl/container/flat_hash_set.h"
 #include "absl/flags/flag.h"
@@ -547,6 +548,7 @@ absl::string_view ConstraintCaseName(
     case ConstraintProto::ConstraintCase::CONSTRAINT_NOT_SET:
       return "kEmpty";
   }
+  ABSL_UNREACHABLE();
 }
 
 std::vector<int> UsedVariables(const ConstraintProto& ct) {
diff --git a/ortools/sat/diffn_util.cc b/ortools/sat/diffn_util.cc
index 7bb8e668d9..31c99b487f 100644
--- a/ortools/sat/diffn_util.cc
+++ b/ortools/sat/diffn_util.cc
@@ -41,7 +41,6 @@
 #include "absl/log/vlog_is_on.h"
 #include "absl/random/bit_gen_ref.h"
 #include "absl/types/span.h"
-#include "ortools/base/logging.h"
 #include "ortools/base/stl_util.h"
 #include "ortools/base/strong_vector.h"
 #include "ortools/graph/connected_components.h"
@@ -1114,6 +1113,7 @@ constexpr const EdgeInfo& GetEdgeInfo(ProbingRectangle::Edge edge) {
     case Edge::TOP:
       return EdgeInfoHolder::kTop;
   }
+  LOG(FATAL) << "Invalid edge: " << static_cast<int>(edge);
 }
 
 IntegerValue GetSmallest1DIntersection(ProbingRectangle::Direction direction,
@@ -1129,6 +1129,7 @@ IntegerValue GetSmallest1DIntersection(ProbingRectangle::Direction direction,
                                     range.bounding_area.y_max, range.y_size,
                                     rectangle.y_min, rectangle.y_max);
   }
+  LOG(FATAL) << "Invalid direction: " << static_cast<int>(direction);
 }
 
 }  // namespace
@@ -1391,6 +1392,7 @@ IntegerValue ProbingRectangle::GetShrinkDeltaArea(Edge edge) const {
     case Edge::TOP:
       return (current_rectangle.y_max - coordinate) * current_rectangle.SizeX();
   }
+  LOG(FATAL) << "Invalid edge: " << static_cast<int>(edge);
 }
 
 void ProbingRectangle::CacheShrinkDeltaEnergy(int dimension) {
@@ -1493,6 +1495,7 @@ bool ProbingRectangle::CanShrink(Edge edge) const {
     case Edge::TOP:
       return (indexes_[Edge::TOP] > next_indexes_[Edge::BOTTOM]);
   }
+  LOG(FATAL) << "Invalid edge: " << static_cast<int>(edge);
 }
 
 namespace {
diff --git a/ortools/sat/diffn_util.h b/ortools/sat/diffn_util.h
index 5291a71b2a..110f8f59fd 100644
--- a/ortools/sat/diffn_util.h
+++ b/ortools/sat/diffn_util.h
@@ -28,14 +28,13 @@
 #include "absl/container/flat_hash_set.h"
 #include "absl/container/inlined_vector.h"
 #include "absl/log/check.h"
+#include "absl/log/log.h"
 #include "absl/random/bit_gen_ref.h"
 #include "absl/strings/str_format.h"
-#include "absl/types/optional.h"
 #include "absl/types/span.h"
 #include "ortools/sat/integer_base.h"
 #include "ortools/sat/scheduling_helpers.h"
 #include "ortools/sat/util.h"
-#include "ortools/util/saturated_arithmetic.h"
 #include "ortools/util/strong_integers.h"
 
 namespace operations_research {
@@ -471,6 +470,7 @@ struct RectangleInRange {
                          .y_min = bounding_area.y_max - y_size,
                          .y_max = bounding_area.y_max};
     }
+    LOG(FATAL) << "Invalid corner: " << static_cast<int>(p);
   }
 
   Rectangle GetBoudingBox() const { return bounding_area; }
diff --git a/ortools/sat/no_overlap_2d_helper.cc b/ortools/sat/no_overlap_2d_helper.cc
index 35f7c08e15..d25712be18 100644
--- a/ortools/sat/no_overlap_2d_helper.cc
+++ b/ortools/sat/no_overlap_2d_helper.cc
@@ -19,6 +19,7 @@
 #include <vector>
 
 #include "absl/base/log_severity.h"
+#include "absl/base/optimization.h"
 #include "absl/log/check.h"
 #include "absl/log/log.h"
 #include "absl/types/span.h"
@@ -188,6 +189,7 @@ bool NoOverlap2DConstraintHelper::PropagateRelativePosition(
       return LeftBoxBeforeRightBoxOnFirstDimension(
           second, first, y_helper_.get(), x_helper_.get());
   }
+  ABSL_UNREACHABLE();
 }
 
 void NoOverlap2DConstraintHelper::Reset(