mc-imperial · afd · Jul 13, 2026 · Jul 13, 2026
diff --git a/src/libdredd/src/mutate_ast_consumer.cc b/src/libdredd/src/mutate_ast_consumer.cc
@@ -397,7 +397,7 @@ std::string MutateAstConsumer::GetRegularDreddPreludeC(
   result << "#elif __APPLE__\n";
   result << "#define thread_local __thread\n";
   result << "#else\n";
-  result << "#include <threads.h>\n";
+  result << "#define thread_local _Thread_local\n";
   result << "#endif\n";
   result << "\n";
   result << "static thread_local int __dredd_some_mutation_enabled = 1;\n";

diff --git a/test/single_file/add.c.expected b/test/single_file/add.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/add.c.noopt.expected b/test/single_file/add.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/add_float.c.expected b/test/single_file/add_float.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/add_float.c.noopt.expected b/test/single_file/add_float.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/add_mul.c.expected b/test/single_file/add_mul.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/add_mul.c.noopt.expected b/test/single_file/add_mul.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/add_type_aliases.c.noopt.expected b/test/single_file/add_type_aliases.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/assign.c.expected b/test/single_file/assign.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/assign.c.noopt.expected b/test/single_file/assign.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/basic.c.expected b/test/single_file/basic.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/basic.c.noopt.expected b/test/single_file/basic.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/binary_long_long_and_long_name_clash.c.noopt.expected b/test/single_file/binary_long_long_and_long_name_clash.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/binary_operands_both_zero.c.expected b/test/single_file/binary_operands_both_zero.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/binary_operands_both_zero.c.noopt.expected b/test/single_file/binary_operands_both_zero.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/bitfield.c.expected b/test/single_file/bitfield.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/bitfield.c.noopt.expected b/test/single_file/bitfield.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/boolean_not_insertion_optimisation.c.expected b/test/single_file/boolean_not_insertion_optimisation.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/boolean_not_insertion_optimisation.c.noopt.expected b/test/single_file/boolean_not_insertion_optimisation.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/comma.c.expected b/test/single_file/comma.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/comma.c.noopt.expected b/test/single_file/comma.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/comma_initialization.c.expected b/test/single_file/comma_initialization.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/comma_initialization.c.noopt.expected b/test/single_file/comma_initialization.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/comma_side_effects.c.expected b/test/single_file/comma_side_effects.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/comma_side_effects.c.noopt.expected b/test/single_file/comma_side_effects.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/const_sized_array_int.c.expected b/test/single_file/const_sized_array_int.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/const_sized_array_int.c.noopt.expected b/test/single_file/const_sized_array_int.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/define_at_start_of_file.c.expected b/test/single_file/define_at_start_of_file.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/define_at_start_of_file.c.noopt.expected b/test/single_file/define_at_start_of_file.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/define_in_first_decl.c.expected b/test/single_file/define_in_first_decl.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/define_in_first_decl.c.noopt.expected b/test/single_file/define_in_first_decl.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/do_not_mutate_under_sizeof.c.expected b/test/single_file/do_not_mutate_under_sizeof.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/do_not_mutate_under_sizeof.c.noopt.expected b/test/single_file/do_not_mutate_under_sizeof.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/enum.c.noopt.expected b/test/single_file/enum.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/expr_lvalue.c.expected b/test/single_file/expr_lvalue.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/expr_lvalue.c.noopt.expected b/test/single_file/expr_lvalue.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/expr_macro.c.expected b/test/single_file/expr_macro.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/expr_macro.c.noopt.expected b/test/single_file/expr_macro.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/float_binary_opts.c.expected b/test/single_file/float_binary_opts.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/float_binary_opts.c.noopt.expected b/test/single_file/float_binary_opts.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/float_unary_opt.c.expected b/test/single_file/float_unary_opt.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/float_unary_opt.c.noopt.expected b/test/single_file/float_unary_opt.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/floats.c.expected b/test/single_file/floats.c.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;

diff --git a/test/single_file/floats.c.noopt.expected b/test/single_file/floats.c.noopt.expected
@@ -17,7 +17,7 @@
 #elif __APPLE__
 #define thread_local __thread
 #else
-#include <threads.h>
+#define thread_local _Thread_local
 #endif
 
 static thread_local int __dredd_some_mutation_enabled = 1;