Compile mesa with vs2026 failed!

[UMU618]

Describe the bug
Compile mesa with vs2026 backend failed!

To Reproduce

git clone git@ssh.gitlab.freedesktop.org:mesa/mesa.git
cd mesa
meson setup mesa.build . --backend=vs

Expected behavior

should be secceeded just as vs2022

log:

**********************************************************************
** Visual Studio 2026 Developer Command Prompt v18.1.1
** Copyright (c) 2025 Microsoft Corporation
**********************************************************************
[DEBUG:ext\vcvars.bat] Found potential v145 version file: 'Microsoft.VCToolsVersion.VC.14.50.18.0.txt'
[DEBUG:ext\vcvars.bat] Testing v145 version file: 'Microsoft.VCToolsVersion.VC.14.50.18.0.txt'
[vcvarsall.bat] Environment initialized for: 'x64'
The Meson build system
Version: 1.10.0
Source dir: D:\freedesktop\mesa\mesa
Build dir: D:\freedesktop\mesa\mesa\mesa.build_x64_release
Build type: native build
Auto detected Visual Studio backend: vs2026
Project name: mesa
Project version: 26.0.0-devel
C compiler for the host machine: cl (msvc 19.50.35721 "Microsoft (R) C/C++ Optimizing Compiler Version 19.50.35721 for x64")
C linker for the host machine: link link 14.50.35721.0
C++ compiler for the host machine: cl (msvc 19.50.35721 "Microsoft (R) C/C++ Optimizing Compiler Version 19.50.35721 for x64")
C++ linker for the host machine: link link 14.50.35721.0
Host machine cpu family: x86_64
Host machine cpu: x86_64
Checking for size of "void*" : 8
Checking if "-mtls-dialect=gnu2" runs: DID NOT COMPILE
Checking if "-mtls-dialect=desc" runs: DID NOT COMPILE
Dependency libglvnd skipped: feature glvnd disabled
Program glslangValidator found: NO
Dependency libva-win32 skipped: feature gallium-va disabled
Program python3 found: YES 3.11.8 3.11.8 (D:\g\depot_tools\python3.BAT)
Fetching value of define "ETIME" : 137
Compiler for C supports arguments -gsplit-dwarf: NO
Compiler for C supports link arguments -Wl,--gdb-index: NO
Checking for function "bswap32" : NO
Checking for function "bswap64" : NO
Checking for function "clz" : NO
Checking for function "clzll" : NO
Checking for function "ctz" : NO
Checking for function "expect" : NO
Checking for function "ffs" : NO
Checking for function "ffsll" : NO
Checking for function "popcount" : NO
Checking for function "popcountll" : NO
Checking for function "unreachable" : NO
Checking for function "types_compatible_p" : NO
Checking for function "__builtin_add_overflow" : NO
Checking for function "__builtin_add_overflow_p" : NO
Checking for function "__builtin_sub_overflow_p" : NO
Compiler for C supports function attribute const: NO
Compiler for C supports function attribute flatten: NO
Compiler for C supports function attribute malloc: NO
Compiler for C supports function attribute pure: NO
Compiler for C supports function attribute unused: NO
Compiler for C supports function attribute warn_unused_result: NO
Compiler for C supports function attribute weak: NO
Compiler for C supports function attribute format: NO
Compiler for C supports function attribute packed: NO
Compiler for C supports function attribute returns_nonnull: NO
Compiler for C supports function attribute alias: NO
Compiler for C supports function attribute noreturn: NO
Compiler for C supports function attribute optimize: NO
Compiler for C supports function attribute cold: NO
Compiler for C supports function attribute visibility:hidden: NO
Checking if "__uint128_t" compiles: NO
Checking for function "reallocarray" : NO
Checking for function "fmemopen" : NO
Compiler for C supports arguments /wd4018: YES
Compiler for C supports arguments /wd4056: YES
Compiler for C supports arguments /wd4244: YES
Compiler for C supports arguments /wd4267: YES
Compiler for C supports arguments /wd4305: YES
Compiler for C supports arguments /wd4351: YES
Compiler for C supports arguments /wd4756: YES
Compiler for C supports arguments /wd4800: YES
Compiler for C supports arguments /wd4291: YES
Compiler for C supports arguments /wd4146: YES
Compiler for C supports arguments /wd4200: YES
Compiler for C supports arguments /wd4624: YES
Compiler for C supports arguments /wd4309: YES
Compiler for C supports arguments /wd4838: YES
Compiler for C supports arguments /wd5105: YES
Compiler for C supports arguments /we4020: YES
Compiler for C supports arguments /we4024: YES
Compiler for C supports arguments /we4189: YES
Compiler for C supports arguments /Zc:__cplusplus: YES
Compiler for C supports arguments /Zc:enumTypes: YES
Compiler for C supports arguments /Zc:preprocessor: YES
Compiler for C++ supports arguments /wd4018: YES
Compiler for C++ supports arguments /wd4056: YES
Compiler for C++ supports arguments /wd4244: YES
Compiler for C++ supports arguments /wd4267: YES
Compiler for C++ supports arguments /wd4305: YES
Compiler for C++ supports arguments /wd4351: YES
Compiler for C++ supports arguments /wd4756: YES
Compiler for C++ supports arguments /wd4800: YES
Compiler for C++ supports arguments /wd4291: YES
Compiler for C++ supports arguments /wd4146: YES
Compiler for C++ supports arguments /wd4200: YES
Compiler for C++ supports arguments /wd4624: YES
Compiler for C++ supports arguments /wd4309: YES
Compiler for C++ supports arguments /wd4838: YES
Compiler for C++ supports arguments /wd5105: YES
Compiler for C++ supports arguments /we4020: YES
Compiler for C++ supports arguments /we4024: YES
Compiler for C++ supports arguments /we4189: YES
Compiler for C++ supports arguments /Zc:__cplusplus: YES
Compiler for C++ supports arguments /Zc:enumTypes: YES
Compiler for C++ supports arguments /Zc:preprocessor: YES
Checking for function "__builtin_ia32_clflushopt" : NO
Checking if "GCC atomic builtins" compiles: NO
Checking if "GCC 64bit atomics" with dependency  links: NO
Library ws2_32 found: YES
Header "sys/sysmacros.h" has symbol "major" : NO
Header "sys/mkdev.h" has symbol "major" : NO
Check usable header "sched.h" : NO
Check usable header "sys/sysctl.h" : NO
Check usable header "xlocale.h" : NO
Check usable header "linux/futex.h" : NO
Check usable header "endian.h" : NO
Check usable header "dlfcn.h" : NO
Check usable header "sys/shm.h" : NO
Check usable header "cet.h" : NO
Check usable header "pthread_np.h" : NO
Check usable header "sys/inotify.h" : NO
Check usable header "linux/udmabuf.h" : NO
Checking for function "strtof" : YES
Checking for function "mkostemp" : NO
Checking for function "memfd_create" : NO
Checking for function "random_r" : NO
Checking for function "flock" : NO
Checking for function "strtok_r" : NO
Checking for function "getrandom" : NO
Checking for function "qsort_s" : YES
Checking for function "posix_fallocate" : NO
Checking for function "secure_getenv" : NO
Checking for function "sysconf" : NO
Checking if "GNU qsort_r" links: NO
Checking if "BSD qsort_r" links: NO
Header "time.h" has symbol "struct timespec" : YES
Checking for function "thrd_create" : YES
Header "errno.h" has symbol "program_invocation_name" : NO
Header "math.h" has symbol "issignaling" : NO
Checking whether type "struct dirent" has member "d_type" : NO
Checking if "strtod has locale support" links: NO
Checking if "Bsymbolic" links: NO
Checking if "dynamic-list" links: NO
Compiler for C supports link arguments -Wl,--build-id=sha1: NO
Checking for function "dl_iterate_phdr" : NO
Dependency zlib skipped: feature zlib disabled
Found pkg-config: YES (D:\d\bin\pkg-config.EXE) 0.28
Found CMake: D:\d\CMake\bin\cmake.EXE (4.2.1)
Traceback (most recent call last):
  File "mesonbuild\mesonmain.py", line 193, in run
  File "mesonbuild\msetup.py", line 404, in run
  File "mesonbuild\msetup.py", line 196, in generate
  File "mesonbuild\msetup.py", line 255, in _generate
  File "mesonbuild\interpreter\interpreter.py", line 3063, in run
  File "mesonbuild\interpreterbase\interpreterbase.py", line 178, in run
  File "mesonbuild\interpreterbase\interpreterbase.py", line 203, in evaluate_codeblock
  File "mesonbuild\interpreterbase\interpreterbase.py", line 195, in evaluate_codeblock
  File "mesonbuild\interpreterbase\interpreterbase.py", line 213, in evaluate_statement
  File "mesonbuild\interpreterbase\interpreterbase.py", line 644, in assignment
  File "mesonbuild\interpreterbase\interpreterbase.py", line 209, in evaluate_statement
  File "mesonbuild\interpreterbase\interpreterbase.py", line 536, in function_call
  File "mesonbuild\interpreterbase\decorators.py", line 237, in wrapper
  File "mesonbuild\interpreterbase\decorators.py", line 565, in wrapper
  File "mesonbuild\interpreterbase\decorators.py", line 85, in wrapped
  File "mesonbuild\interpreter\interpreter.py", line 1788, in func_dependency
  File "mesonbuild\interpreter\dependencyfallbacks.py", line 364, in lookup
  File "mesonbuild\interpreter\dependencyfallbacks.py", line 97, in _do_dependency
  File "mesonbuild\dependencies\detect.py", line 115, in find_external_dependency
  File "mesonbuild\dependencies\cmake.py", line 119, in __init__
  File "mesonbuild\dependencies\cmake.py", line 153, in _get_cmake_info
  File "mesonbuild\cmake\toolchain.py", line 61, in write
  File "mesonbuild\cmake\toolchain.py", line 104, in generate
  File "mesonbuild\cmake\toolchain.py", line 249, in update_cmake_compiler_state
  File "mesonbuild\cmake\common.py", line 111, in cmake_get_generator_args
AssertionError

meson.build:1621:11: ERROR: Unhandled python exception

    This is a Meson bug and should be reported!
适用于 .NET Framework MSBuild 版本 18.0.5+e22287bf1
MSBUILD : error MSB1009: 项目文件不存在。
开关:mesa.build_x64_release\mesa.sln
适用于 .NET Framework MSBuild 版本 18.0.5+e22287bf1
MSBUILD : error MSB1009: 项目文件不存在。
开关:mesa.build_x64_release\RUN_INSTALL.vcxproj

system parameters

• a plain native build (for the same computer)
• Windows 11
• Python 3.13.5
• meson 1.10.0
• ninja 1.12.1

[dcbaker]

Just to help narrow things down, can you try with the ninja backend? I'd like to try to narrow this down to a compiler issue or a backend issue.

[UMU618]

Just to help narrow things down, can you try with the ninja backend? I'd like to try to narrow this down to a compiler issue or a backend issue.

FYI: --backend=vs2022 is OK.

This is a MSVC build, and I don't have clang installed, so --backend=ninja is failed early.

[lb90]

Maybe we only have to add a VS2026 entry in https://github.com/mesonbuild/meson/blob/master/mesonbuild/cmake/common.py#L38. Could you try, @UMU618?