msvc 2022 + /O1 cannot generate correct instructions

[waruqi]

When I use msvc 2022 and set the /O1 optimization option, the compiler generates wrong instructions, causing reading the file to always return 0.

https://developercommunity.visualstudio.com/t/Codegen-bug-on-x64-with-O1-optimize/10825899

#include <stdio.h>
#include <windows.h>

int main(int argc, char** argv) {
    HANDLE file = CreateFileW(L"D:/a.cpp", GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
    if (file != INVALID_HANDLE_VALUE) {
        
        DWORD read = 2; // set a initial value, just to verify the optimization results
        BYTE data[8196];
        __int64 r = ReadFile((HANDLE)file, data, (DWORD)sizeof(data), &read, NULL)? (__int64)read : -1;
        printf("Read: %d, toInt64: %lld r: %lld\n", read, (unsigned __int64)read, r);
        CloseHandle(file);
    }
    return 0;
}

target("testf")
    set_kind("binary")
    add_files("src/*.c")
    add_cxflags("/O1")

PS C:\Users\wangrunqing\Downloads\testf> xmake -rv
checking for cl.exe ... C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Tools\MSVC\14.43.34618\bin\HostX64\x64\cl.exe
checking for Microsoft Visual Studio (x64) version ... 2022
checking for Microsoft C/C++ Compiler (x64) version ... 19.43.34618
checking for nim ... no
checking for nim ... no
checking for link.exe ... C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Tools\MSVC\14.43.34618\bin\HostX64\x64\link.exe
checking for the linker (ld) ... link.exe
checking for cl.exe ... C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Tools\MSVC\14.43.34618\bin\HostX64\x64\cl.exe
checking for the c compiler (cc) ... cl.exe
checking for C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Tools\MSVC\14.43.34618\bin\HostX64\x64\cl.exe ... ok
checking for flags (/O1) ... ok
checking for cl.exe ... C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Tools\MSVC\14.43.34618\bin\HostX64\x64\cl.exe
checking for the c++ compiler (cxx) ... cl.exe
[ 50%]: compiling.release src\main.c
"C:\\Program Files\\Microsoft Visual Studio\\2022\\Preview\\VC\\Tools\\MSVC\\14.43.34618\\bin\\HostX64\\x64\\cl.exe" -c -nologo /O1 -Fobuild\.objs\testf\windows\x64\release\src\main.c.obj src\main.c
checking for flags (cl_sourceDependencies) ... ok
[ 75%]: linking.release testf.exe
"C:\\Program Files\\Microsoft Visual Studio\\2022\\Preview\\VC\\Tools\\MSVC\\14.43.34618\\bin\\HostX64\\x64\\link.exe" -nologo -dynamicbase -nxcompat -machine:x64 -out:build\windows\x64\release\testf.exe build\.objs\testf\windows\x64\release\src\main.c.obj
[100%]: build ok, spent 0.907s
PS C:\Users\wangrunqing\Downloads\testf> xmake r
Read: 138, toInt64: 2 r: 2 <--- use incorrect initial value

tbox/src/tbox/platform/windows/file.c

Lines 150 to 159 in 8fe64e4

	tb_long_t tb_file_read(tb_file_ref_t file, tb_byte_t* data, tb_size_t size)
	{
	// check
	tb_assert_and_check_return_val(file && data, -1);
	tb_check_return_val(size, 0);
	// read
	DWORD real_size = 0;
	return ReadFile((HANDLE)file, data, (DWORD)size, &real_size, tb_null)? (tb_long_t)real_size : -1;
	}

tb_long_t -> __init64 here

[waruqi]

tb_long_t tb_file_read(tb_file_ref_t file, tb_byte_t* data, tb_size_t size)
{
    // check
    tb_assert_and_check_return_val(file && data, -1);
    tb_check_return_val(size, 0);
    
    // read
    DWORD real_size = 2;
    __int64 r = ReadFile((HANDLE)file, data, (DWORD)size, &real_size, tb_null)? (__int64)real_size : -1;
    tb_trace_i("real: %d real64: %lld ret: %lld\n", real_size, (__int64)real_size, r);
    return r;
}

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[Juvwxyz]

This bug has been reported to the Microsoft C++ team. https://developercommunity.visualstudio.com/t/Codegen-bug-on-x64-with-O1-optimize/10825899

[waruqi]

It does not work for vs2022 on windows arm64 + /O2 too.

xmake-io/xmake-repo#6912 (comment)

https://github.com/waruqi/github-action-setup-xmake/actions/runs/14519127135

checking for Microsoft Visual Studio (arm64) version ... 2022
checking for Microsoft C/C++ Compiler (arm64) version ... 19.43.34808