Test ignored-error storage across translation units

CMakeLists.txt

@@ -158,18 +158,10 @@ add_custom_command(
   VERBATIM
 )
 
-# More than one library target consumes the generated sources below. Route
-# them through one explicit prerequisite so parallel Make builds cannot invoke
-# the same generator twice and interleave writes to errno.c.
-add_custom_target(akerror_generated
-  DEPENDS ${GENERATED_ERRNO_C} ${GENERATED_AKERROR_H}
-)
-
 add_library(akerror SHARED
   src/error.c
   ${GENERATED_ERRNO_C}
 )
-add_dependencies(akerror akerror_generated)
 
 target_include_directories(akerror PUBLIC
   $<BUILD_INTERFACE:${GENERATED_DIR}/include>
@@ -208,32 +200,6 @@ set_target_properties(akerror PROPERTIES
 akerr_instrument_for_coverage(akerror)
 akerr_instrument_for_sanitizers(akerror)
 
-# akerr_init() must terminate if it cannot reserve the library-owned status
-# band. The production table sizes are deliberately PRIVATE, so exercise that
-# otherwise unreachable startup failure with a second library target whose
-# private registries cannot accept even the first reservation. Keeping this a
-# distinct target is the test: no compile definition leaks into consumers or
-# weakens the production library.
-add_library(akerror_init_failure SHARED
-  src/error.c
-  ${GENERATED_ERRNO_C}
-)
-add_dependencies(akerror_init_failure akerror_generated)
-target_include_directories(akerror_init_failure PUBLIC
-  ${GENERATED_DIR}/include
-)
-target_compile_definitions(akerror_init_failure
-  PUBLIC AKERR_USE_STDLIB=${AKERR_USE_STDLIB}
-  PRIVATE AKERR_STATUS_NAME_SLOTS=8
-  PRIVATE AKERR_MAX_RESERVED_STATUS_RANGES=0
-  PRIVATE ${AKERR_THREADS_DEFINE}
-)
-if(AKERR_THREAD_SAFE)
-    target_link_libraries(akerror_init_failure PRIVATE Threads::Threads)
-endif()
-akerr_instrument_for_coverage(akerror_init_failure)
-akerr_instrument_for_sanitizers(akerror_init_failure)
-
 # Each test is one source file in tests/ built into test_<name> and registered
 # as CTest <name>. Tests expected to abort (unhandled error / contract
 # violation) go in AKERR_WILL_FAIL_TESTS; all others must exit 0.
@@ -261,7 +227,6 @@ set(AKERR_TESTS
     err_registry_init_order
     err_status_exception
     err_copy_string
-    err_init_reservation_fatal
     err_library_status_fatal
     err_refcount_double_fail
     err_stacktrace_bounds
@@ -289,18 +254,13 @@ endif()
 set(AKERR_WILL_FAIL_TESTS
     err_trace
     err_improper_closure
-    err_init_reservation_fatal
     err_library_status_fatal
 )
 
 foreach(_test IN LISTS AKERR_TESTS)
     add_executable(test_${_test} tests/${_test}.c)
     target_include_directories(test_${_test} PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/tests)
-    if(_test STREQUAL "err_init_reservation_fatal")
-        target_link_libraries(test_${_test} PRIVATE akerror_init_failure)
-    else()
     target_link_libraries(test_${_test} PRIVATE akerror)
-    endif()
     if(AKERR_THREAD_SAFE)
         target_link_libraries(test_${_test} PRIVATE Threads::Threads)
     endif()
@@ -322,6 +282,22 @@ foreach(_test IN LISTS AKERR_TESTS)
     endif()
 endforeach()
 
+# The ignored-error slot is declared in the public header but must have one
+# library definition. Compare its address from two translation units, and
+# compile the consumer-facing test with all ordinary warnings enabled: a
+# header-local TLS definition would both duplicate storage and warn when unused.
+add_executable(test_err_ignore_multitu
+               tests/err_ignore_multitu.c
+               tests/err_ignore_multitu_helper.c)
+target_include_directories(test_err_ignore_multitu
+                           PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/tests)
+target_link_libraries(test_err_ignore_multitu PRIVATE akerror)
+target_compile_options(test_err_ignore_multitu PRIVATE -Wall -Wextra -Werror)
+if(AKERR_THREAD_SAFE)
+    target_link_libraries(test_err_ignore_multitu PRIVATE Threads::Threads)
+endif()
+add_test(NAME err_ignore_multitu COMMAND test_err_ignore_multitu)
+
 # HANDLE_GROUP deliberately enters the next case label. Keep that public macro
 # compiling with the warning enabled, so a future macro edit cannot restore the
 # warning for consumers which adopt -Wextra.

src/error.c

@@ -88,10 +88,7 @@ typedef struct
 
 static akerr_StatusName akerr_status_names[AKERR_STATUS_NAME_SLOTS];
 static int akerr_status_name_count;
-/* C has no portable zero-length arrays. Keep one unused physical slot when a
- * test build sets the logical capacity to zero to drive init's fatal path. */
-static akerr_StatusRange akerr_status_ranges[
-    AKERR_MAX_RESERVED_STATUS_RANGES > 0 ? AKERR_MAX_RESERVED_STATUS_RANGES : 1];
+static akerr_StatusRange akerr_status_ranges[AKERR_MAX_RESERVED_STATUS_RANGES];
 static int akerr_status_range_count;
 
 akerr_ErrorContext AKERR_ARRAY_ERROR[AKERR_MAX_ARRAY_ERROR];

tests/err_ignore_multitu.c

@@ -0,0 +1,18 @@
+#include "akerror.h"
+#include "err_ignore_multitu.h"
+#include <stdio.h>
+
+int main(void)
+{
+    akerr_ErrorContext **main_address = &__akerr_last_ignored;
+    akerr_ErrorContext **helper_address = akerr_multitu_snapshot_address();
+
+    if ( main_address != helper_address ) {
+	fprintf(stderr,
+		"CHECK FAILED: ignored-error storage differs between translation units\n");
+	return 1;
+    }
+
+    fprintf(stderr, "err_ignore_multitu ok\n");
+    return 0;
+}

tests/err_ignore_multitu.h

@@ -0,0 +1,8 @@
+#ifndef AKERR_TEST_IGNORE_MULTITU_H
+#define AKERR_TEST_IGNORE_MULTITU_H
+
+#include "akerror.h"
+
+akerr_ErrorContext **akerr_multitu_snapshot_address(void);
+
+#endif

tests/err_ignore_multitu_helper.c

@@ -0,0 +1,6 @@
+#include "err_ignore_multitu.h"
+
+akerr_ErrorContext **akerr_multitu_snapshot_address(void)
+{
+    return &__akerr_last_ignored;
+}

tests/err_init_reservation_fatal.c

@@ -1,20 +0,0 @@
-#include "akerror.h"
-
-#include <stdio.h>
-
-/*
- * This executable links to akerror_init_failure, a test-only library target
- * with no status-range slots. The first reservation in akerr_init() must be
- * terminal: continuing would leave every library status unowned and make all
- * subsequent name registrations invalid.
- *
- * CTest marks this WILL_FAIL. Reaching the message and returning zero means
- * initialization swallowed its own reservation failure.
- */
-int main(void)
-{
-    akerr_init();
-
-    fprintf(stderr, "err_init_reservation_fatal: akerr_init did not terminate\n");
-    return 0;
-}