v.builder: always apply -fno-strict-aliasing too, on -cc gcc -prod to avoid the need for the -cflags -fno-inline-small-functions workaround with gcc > 12.0 (fix #26512)

[spytheman]

Fix #26512.
Thank you @tankf33der for investigating it more completely.

[tankf33der]

I have access to Debian 13.3, gcc is 14.2.0-19.

I took the effort to show the current situation with the tests.

./v test vlib/

To reproduce just failure 1 run:    '/home/tankf33der/v/v'  '/home/tankf33der/v/vlib/v/generics/new_generics_regression_test.v'
Summary for all V _test.v files: 1 failed, 2630 passed, 61 skipped, 2692 total. Elapsed time: 64700 ms, on 127 parallel jobs. Comptime: 2189294 ms. Runtime: 596752 ms.

./v -cc gcc -prod test vlib/

...
...
 OK    [2689/2692] C: 51595.5 ms, R:    13.590 ms vlib/veb/tests/middleware_test.v
 OK    [2690/2692] C: 22289.3 ms, R: 30943.237 ms vlib/veb/tests/memory_leak_test.v
 OK    [2691/2692] C:  5792.6 ms, R: 154468.500 ms vlib/v/slow_tests/keep_args_alive_test.c.v
 OK    [2692/2692] C: 63410.6 ms, R:     9.132 ms vlib/v/transformer/tests/const_infix_expr_test.v
--------------------------------------------------------------------------------------------------------------------------------------------
To reproduce just failure 1 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/crypto/ecdsa/example/ensure_compatibility_with_net_openssl_test.v'
To reproduce just failure 2 run:    '/home/tankf33der/v/v' -cc gcc -prod -w '/home/tankf33der/v/vlib/json/tests/json_encode_default_option_none_test.v'
To reproduce just failure 3 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/encoding/xml/query_test.v'
To reproduce just failure 4 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/json/tests/json_decode_with_sumtype_test.v'
To reproduce just failure 5 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/encoding/xml/test/local/13_doctype_element/doctype_test.v'
To reproduce just failure 6 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/json/tests/json_encode_primite_test.v'
To reproduce just failure 7 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/json/tests/json_sumtype_test.v'
To reproduce just failure 8 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/json/tests/json_test.v'
To reproduce just failure 9 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/encoding/binary/serialize_test.v'
To reproduce just failure 10 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/os/find_abs_path_of_executable_test.v'
To reproduce just failure 11 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/net/jsonrpc/jsonrpc_test.v'
To reproduce just failure 12 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/os/dir_expansions_test.v'
To reproduce just failure 13 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/strconv/converter_test.v'
To reproduce just failure 14 run:    '/home/tankf33der/v/v' -cc gcc -prod  -b c '/home/tankf33der/v/vlib/os/os_test.c.v'
To reproduce just failure 15 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/regex/pcre/regex_test.v'
To reproduce just failure 16 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/toml/scanner/scanner_test.v'
To reproduce just failure 17 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/v/build_constraint/constraint_test.v'
To reproduce just failure 18 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/toml/tests/compact_test.v'
To reproduce just failure 19 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/toml/tests/nested_test.v'
To reproduce just failure 20 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/toml/tests/table_test.v'
To reproduce just failure 21 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/toml/tests/strings_test.v'
To reproduce just failure 22 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/toml/tests/toml_test.v'
To reproduce just failure 23 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/v/tests/assign/assign_option_of_multi_return_with_heap_test.v'
To reproduce just failure 24 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/v/generics/new_generics_regression_test.v'
To reproduce just failure 25 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/v/tests/builtin_maps/map_and_array_with_fns_test.v'
To reproduce just failure 26 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/net/http/server_test.v'
To reproduce just failure 27 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/v/tests/comptime/comptime_map_generic_test.v'
To reproduce just failure 28 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/x/crypto/curve25519/usage_test.v'
To reproduce just failure 29 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/x/encoding/asn1/ia5string_test.v'
To reproduce just failure 30 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/x/encoding/asn1/element_decode_test.v'
To reproduce just failure 31 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/x/encoding/asn1/public_api_test.v'
To reproduce just failure 32 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/x/json2/tests/decode_array_array_test.v'
To reproduce just failure 33 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/x/json2/tests/decode_object_test.v'
To reproduce just failure 34 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/x/encoding/asn1/integer_test.v'
To reproduce just failure 35 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/x/json2/tests/attributes_test.v'
To reproduce just failure 36 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/x/json2/tests/decode_custom_test.v'
To reproduce just failure 37 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/x/json2/tests/json2_test.v'
To reproduce just failure 38 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/x/json2/tests/json2_tests/json2_test.v'
To reproduce just failure 39 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/x/json2/tests/json_sumtype_test.v'
To reproduce just failure 40 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/veb/tests/handle_split_requests_in_chrome_test.v'
To reproduce just failure 41 run:    '/home/tankf33der/v/v' -cc gcc -prod '/home/tankf33der/v/vlib/vweb/csrf/csrf_test.v'
Summary for all V _test.v files: 41 failed, 2583 passed, 68 skipped, 2692 total. Elapsed time: 197828 ms, on 127 parallel jobs. Comptime: 18729479 ms. Runtime: 606374

./v -cc gcc -cflags -fno-strict-aliasing -prod test vlib/

...
...
 OK    [2691/2692] C: 23953.6 ms, R: 30929.263 ms vlib/veb/tests/memory_leak_test.v
 OK    [2692/2692] C: 62383.9 ms, R:     9.186 ms vlib/v/transformer/tests/const_infix_expr_test.v
--------------------------------------------------------------------------------------------------------------------------------------------
To reproduce just failure 1 run:    '/home/tankf33der/v/v' -cc gcc -cflags -fno-strict-aliasing -prod -w '/home/tankf33der/v/vlib/json/tests/json_encode_default_option_none_test.v'
To reproduce just failure 2 run:    '/home/tankf33der/v/v' -cc gcc -cflags -fno-strict-aliasing -prod '/home/tankf33der/v/vlib/strconv/converter_test.v'
To reproduce just failure 3 run:    '/home/tankf33der/v/v' -cc gcc -cflags -fno-strict-aliasing -prod '/home/tankf33der/v/vlib/v/generics/new_generics_regression_test.v'
To reproduce just failure 4 run:    '/home/tankf33der/v/v' -cc gcc -cflags -fno-strict-aliasing -prod '/home/tankf33der/v/vlib/v/tests/builtin_maps/map_and_array_with_fns_test.v'
Summary for all V _test.v files: 4 failed, 2620 passed, 68 skipped, 2692 total. Elapsed time: 198349 ms, on 127 parallel jobs. Comptime: 19206430 ms. Runtime: 439818 ms.

[spytheman]

I am not sure I understand the purpose of those comparisons.
With the current PR, -prod with gcc will always also use -fno-strict-aliasing .

What is the additional -cflags -fno-strict-aliasing for?

Are you doing the tests on master, or on this branch?

[tankf33der]

@spytheman
I was sleepy and lazy to switch to the PR's branch, so I quickly did everything manually.

[spytheman]

@tankf33der ok, do you think this will be an improvement over the current state?
If you do, I will merge it asap.

The other failing tests are now just 4, and potentially could be caused by another reason, or we may need to change them/tag stuff manually with @[noinline] 🤔 .

[tankf33der]

@spytheman

I don't want to double the bugs and evil, I always have doubts, but when I saw this feature in the nim source code I felt calmer. I vote to do the merge.