#4141 bug-4139 fails for multiple targets

[Gabriele Gorla]

regression test bug-4139 fails for hc08, mcs51-large and mcs51-huge.

[Christopher Bazley]

I'm sorry about the regression.

I believe the cause is shared parameter metadata: an inferred function-pointer type shares the original function’s parameter symbols. Processing the new declaration renames those shared symbols. Copying the parameter list for the inferred type prevents that.

I'll attach a patch as soon as I can.

[Christopher Bazley]

The missing symbol is _next_value_10000_9. The original parameter's storage metadata has been changed while processing the inferred pointer declaration, leaving its generated code referring to unallocated storage. The inferred type and original function share FUNC_ARGS: copyLinkChain copies the function link, but not its parameter values or symbols.

The candidate fix for this regression copies each function declarator's parameter chain in the inferred type. It leaves the original function's symbols intact. There is no need to weaken the existing regression test or make its function reentrant merely to avoid the failure.

All new test cases are in regression. They are valid programs; the required observations are successful linking and correct call results. There are no diagnostic expectations that would justify a valdiag file.

bug-4139.c: reproduces all three reported link failures. After the fix, all 18 assertions pass on each reported target.

bug-4141.c: function conversion, explicit address, copying an inferred pointer, another source function, and direct calls after inference. These tests exercise independent parameter metadata and actual argument passing. A reentrant two-argument function checks parameter order and
values where indirect calls require reentrancy. The call count checks that all expected calls happened. Before the fix this test fails to link on all three reported targets; after it all 12 assertions pass on each.

The new test uses a counter in its callees so HC08 cannot keep every parameter entirely in registers and thereby hide the storage defect.

101 files in valdiag have unchanged results on each of HC08, MCS51 large/stack-auto, STM8 and Z80.

Please consider the attached candidate bug fix.

[Maarten Brock]

I intend to apply this patch.

But I also noticed that the regression tests bug-4139.c, bug-4140.c & bug-4141.c all fail for host with GCC v11.4. Is there a macro that can be checked for these tests?

Running host regression tests
In file included from cases/tst_bug-4139.c:1:
cases/./../tests/bug-4139.c: In function ‘testInferenceConversions’:
cases/./../tests/bug-4139.c:37:10: error: subscripted value is neither array nor pointer nor vector
   37 |   pointer[1] = 7;
      |          ^
In file included from cases/./../tests/bug-4139.c:2,
                 from cases/tst_bug-4139.c:1:
cases/./../tests/bug-4139.c:43:10: error: invalid type argument of unary ‘*’ (have ‘int’)
   43 |   ASSERT(*cursor == 7);
      |          ^~~~~~~
./fwk/include/testfwk.h:140:37: note: in definition of macro ‘ASSERT’
  140 | #define ASSERT(_a)  (++__numTests, (_a) ? (void)0 : __fail ("Assertion failed", #_a, __FILE__, __LINE__))
      |                                     ^~
In file included from cases/tst_bug-4139.c:1:
cases/./../tests/bug-4139.c:47:6: error: subscripted value is neither array nor pointer nor vector
   47 |   row[1][0] = 9;
      |      ^
In file included from cases/./../tests/bug-4139.c:2,
                 from cases/tst_bug-4139.c:1:
cases/./../tests/bug-4139.c:52:10: error: invalid type argument of unary ‘*’ (have ‘int’)
   52 |   ASSERT(*text == 'b');
      |          ^~~~~
./fwk/include/testfwk.h:140:37: note: in definition of macro ‘ASSERT’
  140 | #define ASSERT(_a)  (++__numTests, (_a) ? (void)0 : __fail ("Assertion failed", #_a, __FILE__, __LINE__))
      |                                     ^~
cases/./../tests/bug-4139.c:56:10: error: called object ‘function’ is not a function or function pointer
   56 |   ASSERT(function(4) == 5);
      |          ^~~~~~~~
./fwk/include/testfwk.h:140:37: note: in definition of macro ‘ASSERT’
  140 | #define ASSERT(_a)  (++__numTests, (_a) ? (void)0 : __fail ("Assertion failed", #_a, __FILE__, __LINE__))
      |                                     ^~
In file included from cases/tst_bug-4139.c:1:
cases/./../tests/bug-4139.c:55:8: note: declared here
   55 |   auto function = next;
      |        ^~~~~~~~
In file included from cases/./../tests/bug-4139.c:2,
                 from cases/tst_bug-4139.c:1:
cases/./../tests/bug-4139.c:64:10: error: called object ‘address’ is not a function or function pointer
   64 |   ASSERT(address(6) == 7);
      |          ^~~~~~~
./fwk/include/testfwk.h:140:37: note: in definition of macro ‘ASSERT’
  140 | #define ASSERT(_a)  (++__numTests, (_a) ? (void)0 : __fail ("Assertion failed", #_a, __FILE__, __LINE__))
      |                                     ^~
In file included from cases/tst_bug-4139.c:1:
cases/./../tests/bug-4139.c:63:8: note: declared here
   63 |   auto address = &next;
      |        ^~~~~~~
cases/./../tests/bug-4139.c:72:25: error: incompatible types when initializing type ‘int’ using type ‘struct S’
   72 |   auto aggregate_copy = aggregate;
      |                         ^~~~~~~~~
cases/./../tests/bug-4139.c:73:17: error: request for member ‘member’ in something not a structure or union
   73 |   aggregate_copy.member = 2;
      |                 ^
In file included from cases/./../tests/bug-4139.c:2,
                 from cases/tst_bug-4139.c:1:
cases/./../tests/bug-4139.c:74:24: error: request for member ‘member’ in something not a structure or union
   74 |   ASSERT(aggregate_copy.member == 2);
      |                        ^
./fwk/include/testfwk.h:140:37: note: in definition of macro ‘ASSERT’
  140 | #define ASSERT(_a)  (++__numTests, (_a) ? (void)0 : __fail ("Assertion failed", #_a, __FILE__, __LINE__))
      |                                     ^~
make[3]: *** [Makefile:434: gen/host/tst_bug-4139.o] Fout 1
results/host/tst_bug-4139.out:2:--- FAIL: cannot compile/link cases/tst_bug-4139.c
Failure: cases/tst_bug-4139.c
tst_bug-4139                        (f:  1, t:   1, c:    1, b:       0, T:         0)
In file included from cases/tst_bug-4140.c:1:
cases/./../tests/bug-4140.c: In function ‘testExplicitAutoTypes’:
cases/./../tests/bug-4140.c:84:3: error: static assertion failed: "unsigned char object"
   84 |   _Static_assert(_Generic(&inferred_small, unsigned char *: 1, default: 0), "unsigned char object");
      |   ^~~~~~~~~~~~~~
cases/./../tests/bug-4140.c:85:3: error: static assertion failed: "float object"
   85 |   _Static_assert(_Generic(&inferred_float, float *: 1, default: 0), "float object");
      |   ^~~~~~~~~~~~~~
make[3]: *** [Makefile:434: gen/host/tst_bug-4140.o] Fout 1
results/host/tst_bug-4140.out:2:--- FAIL: cannot compile/link cases/tst_bug-4140.c
Failure: cases/tst_bug-4140.c
tst_bug-4140                        (f:  1, t:   1, c:    1, b:       0, T:         0)
In file included from cases/./../tests/bug-4141.c:2,
                 from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c: In function ‘testInferredFunctionParameters’:
cases/./../tests/bug-4141.c:47:10: error: called object ‘first’ is not a function or function pointer
   47 |   ASSERT(first(4) == 5);
      |          ^~~~~
./fwk/include/testfwk.h:140:37: note: in definition of macro ‘ASSERT’
  140 | #define ASSERT(_a)  (++__numTests, (_a) ? (void)0 : __fail ("Assertion failed", #_a, __FILE__, __LINE__))
      |                                     ^~
In file included from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:45:8: note: declared here
   45 |   auto first = increment;
      |        ^~~~~
In file included from cases/./../tests/bug-4141.c:2,
                 from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:48:10: error: called object ‘second’ is not a function or function pointer
   48 |   ASSERT(second(6) == 7);
      |          ^~~~~~
./fwk/include/testfwk.h:140:37: note: in definition of macro ‘ASSERT’
  140 | #define ASSERT(_a)  (++__numTests, (_a) ? (void)0 : __fail ("Assertion failed", #_a, __FILE__, __LINE__))
      |                                     ^~
In file included from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:46:8: note: declared here
   46 |   auto second = &increment;
      |        ^~~~~~
In file included from cases/./../tests/bug-4141.c:2,
                 from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:53:10: error: called object ‘third’ is not a function or function pointer
   53 |   ASSERT(third(8) == 9);
      |          ^~~~~
./fwk/include/testfwk.h:140:37: note: in definition of macro ‘ASSERT’
  140 | #define ASSERT(_a)  (++__numTests, (_a) ? (void)0 : __fail ("Assertion failed", #_a, __FILE__, __LINE__))
      |                                     ^~
In file included from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:51:8: note: declared here
   51 |   auto third = first;
      |        ^~~~~
In file included from cases/./../tests/bug-4141.c:2,
                 from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:54:10: error: called object ‘other’ is not a function or function pointer
   54 |   ASSERT(other(10) == 9);
      |          ^~~~~
./fwk/include/testfwk.h:140:37: note: in definition of macro ‘ASSERT’
  140 | #define ASSERT(_a)  (++__numTests, (_a) ? (void)0 : __fail ("Assertion failed", #_a, __FILE__, __LINE__))
      |                                     ^~
In file included from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:52:8: note: declared here
   52 |   auto other = decrement;
      |        ^~~~~
In file included from cases/./../tests/bug-4141.c:2,
                 from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:55:10: error: called object ‘first’ is not a function or function pointer
   55 |   ASSERT(first(12) == 13);
      |          ^~~~~
./fwk/include/testfwk.h:140:37: note: in definition of macro ‘ASSERT’
  140 | #define ASSERT(_a)  (++__numTests, (_a) ? (void)0 : __fail ("Assertion failed", #_a, __FILE__, __LINE__))
      |                                     ^~
In file included from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:45:8: note: declared here
   45 |   auto first = increment;
      |        ^~~~~
In file included from cases/./../tests/bug-4141.c:2,
                 from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:56:10: error: called object ‘second’ is not a function or function pointer
   56 |   ASSERT(second(14) == 15);
      |          ^~~~~~
./fwk/include/testfwk.h:140:37: note: in definition of macro ‘ASSERT’
  140 | #define ASSERT(_a)  (++__numTests, (_a) ? (void)0 : __fail ("Assertion failed", #_a, __FILE__, __LINE__))
      |                                     ^~
In file included from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:46:8: note: declared here
   46 |   auto second = &increment;
      |        ^~~~~~
In file included from cases/./../tests/bug-4141.c:2,
                 from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:65:10: error: called object ‘pair’ is not a function or function pointer
   65 |   ASSERT(pair(2, 3) == 23);
      |          ^~~~
./fwk/include/testfwk.h:140:37: note: in definition of macro ‘ASSERT’
  140 | #define ASSERT(_a)  (++__numTests, (_a) ? (void)0 : __fail ("Assertion failed", #_a, __FILE__, __LINE__))
      |                                     ^~
In file included from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:63:8: note: declared here
   63 |   auto pair = combine;
      |        ^~~~
In file included from cases/./../tests/bug-4141.c:2,
                 from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:66:10: error: called object ‘pair_address’ is not a function or function pointer
   66 |   ASSERT(pair_address(4, 5) == 45);
      |          ^~~~~~~~~~~~
./fwk/include/testfwk.h:140:37: note: in definition of macro ‘ASSERT’
  140 | #define ASSERT(_a)  (++__numTests, (_a) ? (void)0 : __fail ("Assertion failed", #_a, __FILE__, __LINE__))
      |                                     ^~
In file included from cases/tst_bug-4141.c:1:
cases/./../tests/bug-4141.c:64:8: note: declared here
   64 |   auto pair_address = &combine;
      |        ^~~~~~~~~~~~
make[3]: *** [Makefile:434: gen/host/tst_bug-4141.o] Fout 1
results/host/tst_bug-4141.out:2:--- FAIL: cannot compile/link cases/tst_bug-4141.c
Failure: cases/tst_bug-4141.c
tst_bug-4141                        (f:  1, t:   1, c:    1, b:       0, T:         0)
Summary for 'host'                   :      3 failures, 31769 tests, 6414 test cases,        0 bytes,          0 ticks
   Failure: cases/tst_bug-4139.c
   Failure: cases/tst_bug-4140.c
   Failure: cases/tst_bug-4141.c