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1115040131claude
1115040131
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claude
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fix(fmtlib.fmt): name module wrapper .cppm so Clang emits the BMI
The generated module wrapper was `mcpp_generated/fmt_module.cc`. On macOS/Windows mcpp drives Clang in gnu mode (`--driver-mode=g++`), where Clang decides "is this a module interface unit?" purely from the file extension: `.cppm`/`.ixx` yes, `.cc` no. A `.cc` module unit still compiles (only the fopen deprecation warning), but Clang silently drops `-fmodule-output` as an unused argument, so no BMI (`fmt.pcm`) is ever written — the consumer's `import fmt;` then fails with `fatal error: module 'fmt' not found`. GCC (Linux) keys off `export module` rather than the extension, so `.cc` happened to work there and masked the bug; nlohmann.json already uses a `.cppm` wrapper, which is why it passed on all three platforms. Rename both the generated_files key and sources to `fmt_module.cppm` to match. Verified end-to-end on Windows (clang 20.1.7, MSVC STL): fmt.pcm is now produced and format_test passes. import std is unrelated and retained. Co-Authored-By: Claude <noreply@anthropic.com>
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Lines changed: 12 additions & 2 deletions

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‎pkgs/f/fmtlib.fmt.lua‎

Lines changed: 12 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -29,6 +29,16 @@
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-- <fmt/*.h>` resolves) and `*/src` (so the tail `#include "format.cc"` /
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-- `"os.cc"` resolve). The wrapper path under mcpp_generated/ is verdir-relative
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-- (no glob), like nlohmann.json / compat.eigen.
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--
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-- The wrapper MUST be named `.cppm`, not `.cc`. On macOS/Windows mcpp drives
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-- Clang in gnu (`--driver-mode=g++`) mode, where Clang decides "is this a module
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-- interface unit?" purely from the file extension: `.cppm`/`.ixx` yes, `.cc` no.
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-- A `.cc` module unit still compiles, but Clang silently drops `-fmodule-output`
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-- as an "unused argument" (-Wunused-command-line-argument), so NO BMI (`fmt.pcm`)
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-- is written — the consumer's `import fmt;` then fails with `module 'fmt' not
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-- found`. GCC (Linux) keys off `export module` instead of the extension, so `.cc`
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-- happened to work there and masked the bug. nlohmann.json already uses `.cppm`;
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-- this matches it.
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package = {
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spec = "1",
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namespace = "fmtlib",
@@ -66,9 +76,9 @@ package = {
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modules = { "fmt" },
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include_dirs = { "*/include", "*/src" },
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generated_files = {
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["mcpp_generated/fmt_module.cc"] = "// Formatting library for C++ - C++20 module\n//\n// Copyright (c) 2012 - present, Victor Zverovich and {fmt} contributors\n// All rights reserved.\n//\n// For the license information refer to format.h.\n\nmodule;\n\n#define FMT_MODULE\n\n#define FMT_IMPORT_STD\n\n#ifdef _MSVC_LANG\n# define FMT_CPLUSPLUS _MSVC_LANG\n#else\n# define FMT_CPLUSPLUS __cplusplus\n#endif\n\n// Put all implementation-provided headers into the global module fragment\n// to prevent attachment to this module.\n#ifndef FMT_IMPORT_STD\n# include <algorithm>\n# include <bitset>\n# include <chrono>\n# include <cmath>\n# include <complex>\n# include <cstddef>\n# include <cstdint>\n# include <cstdio>\n# include <cstdlib>\n# include <cstring>\n# include <ctime>\n# include <exception>\n# if FMT_CPLUSPLUS > 202002L\n# include <expected>\n# endif\n# include <filesystem>\n# include <fstream>\n# include <functional>\n# include <iterator>\n# include <limits>\n# include <locale>\n# include <memory>\n# include <optional>\n# include <ostream>\n# include <source_location>\n# include <stdexcept>\n# include <string>\n# include <string_view>\n# include <system_error>\n# include <thread>\n# include <type_traits>\n# include <typeinfo>\n# include <utility>\n# include <variant>\n# include <vector>\n#else\n# include <limits.h>\n# include <stdint.h>\n# include <stdio.h>\n# include <stdlib.h>\n# include <string.h>\n# include <time.h>\n#endif\n#include <cerrno>\n#include <climits>\n#include <version>\n\n#if __has_include(<cxxabi.h>)\n# include <cxxabi.h>\n#endif\n#if defined(_MSC_VER) || defined(__MINGW32__)\n# include <intrin.h>\n#endif\n#if defined __APPLE__ || defined(__FreeBSD__)\n# include <xlocale.h>\n#endif\n#if __has_include(<winapifamily.h>)\n# include <winapifamily.h>\n#endif\n#if (__has_include(<fcntl.h>) || defined(__APPLE__) || \\\n defined(__linux__)) && \\\n (!defined(WINAPI_FAMILY) || (WINAPI_FAMILY == WINAPI_FAMILY_DESKTOP_APP))\n# include <fcntl.h>\n# include <sys/stat.h>\n# include <sys/types.h>\n# ifndef _WIN32\n# include <unistd.h>\n# else\n# include <io.h>\n# endif\n#endif\n#ifdef _WIN32\n# if defined(__GLIBCXX__)\n# include <ext/stdio_filebuf.h>\n# include <ext/stdio_sync_filebuf.h>\n# endif\n# define WIN32_LEAN_AND_MEAN\n# include <windows.h>\n#endif\n\nexport module fmt;\n\nimport std;\n\n#define FMT_EXPORT export\n#define FMT_BEGIN_EXPORT export {\n#define FMT_END_EXPORT }\n\n// If you define FMT_ATTACH_TO_GLOBAL_MODULE\n// - all declarations are detached from module 'fmt'\n// - the module behaves like a traditional static library, too\n// - all library symbols are mangled traditionally\n// - you can mix TUs with either importing or #including the {fmt} API\n#ifdef FMT_ATTACH_TO_GLOBAL_MODULE\nextern \"C++\" {\n#endif\n\n#ifndef FMT_OS\n# define FMT_OS 1\n#endif\n\n// All library-provided declarations and definitions must be in the module\n// purview to be exported.\n#include \"fmt/args.h\"\n#include \"fmt/chrono.h\"\n#include \"fmt/color.h\"\n#include \"fmt/compile.h\"\n#include \"fmt/format.h\"\n#if FMT_OS\n# include \"fmt/os.h\"\n#endif\n#include \"fmt/ostream.h\"\n#include \"fmt/printf.h\"\n#include \"fmt/ranges.h\"\n#include \"fmt/std.h\"\n#include \"fmt/xchar.h\"\n\n#ifdef FMT_ATTACH_TO_GLOBAL_MODULE\n}\n#endif\n\n#ifdef FMT_ATTACH_TO_GLOBAL_MODULE\nextern \"C++\" {\n#endif\n\n#if FMT_HAS_INCLUDE(\"format.cc\")\n# include \"format.cc\"\n#endif\n#if FMT_OS && FMT_HAS_INCLUDE(\"os.cc\")\n# include \"os.cc\"\n#endif\n\n#ifdef FMT_ATTACH_TO_GLOBAL_MODULE\n}\n#endif\n",
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["mcpp_generated/fmt_module.cppm"] = "// Formatting library for C++ - C++20 module\n//\n// Copyright (c) 2012 - present, Victor Zverovich and {fmt} contributors\n// All rights reserved.\n//\n// For the license information refer to format.h.\n\nmodule;\n\n#define FMT_MODULE\n\n#define FMT_IMPORT_STD\n\n#ifdef _MSVC_LANG\n# define FMT_CPLUSPLUS _MSVC_LANG\n#else\n# define FMT_CPLUSPLUS __cplusplus\n#endif\n\n// Put all implementation-provided headers into the global module fragment\n// to prevent attachment to this module.\n#ifndef FMT_IMPORT_STD\n# include <algorithm>\n# include <bitset>\n# include <chrono>\n# include <cmath>\n# include <complex>\n# include <cstddef>\n# include <cstdint>\n# include <cstdio>\n# include <cstdlib>\n# include <cstring>\n# include <ctime>\n# include <exception>\n# if FMT_CPLUSPLUS > 202002L\n# include <expected>\n# endif\n# include <filesystem>\n# include <fstream>\n# include <functional>\n# include <iterator>\n# include <limits>\n# include <locale>\n# include <memory>\n# include <optional>\n# include <ostream>\n# include <source_location>\n# include <stdexcept>\n# include <string>\n# include <string_view>\n# include <system_error>\n# include <thread>\n# include <type_traits>\n# include <typeinfo>\n# include <utility>\n# include <variant>\n# include <vector>\n#else\n# include <limits.h>\n# include <stdint.h>\n# include <stdio.h>\n# include <stdlib.h>\n# include <string.h>\n# include <time.h>\n#endif\n#include <cerrno>\n#include <climits>\n#include <version>\n\n#if __has_include(<cxxabi.h>)\n# include <cxxabi.h>\n#endif\n#if defined(_MSC_VER) || defined(__MINGW32__)\n# include <intrin.h>\n#endif\n#if defined __APPLE__ || defined(__FreeBSD__)\n# include <xlocale.h>\n#endif\n#if __has_include(<winapifamily.h>)\n# include <winapifamily.h>\n#endif\n#if (__has_include(<fcntl.h>) || defined(__APPLE__) || \\\n defined(__linux__)) && \\\n (!defined(WINAPI_FAMILY) || (WINAPI_FAMILY == WINAPI_FAMILY_DESKTOP_APP))\n# include <fcntl.h>\n# include <sys/stat.h>\n# include <sys/types.h>\n# ifndef _WIN32\n# include <unistd.h>\n# else\n# include <io.h>\n# endif\n#endif\n#ifdef _WIN32\n# if defined(__GLIBCXX__)\n# include <ext/stdio_filebuf.h>\n# include <ext/stdio_sync_filebuf.h>\n# endif\n# define WIN32_LEAN_AND_MEAN\n# include <windows.h>\n#endif\n\nexport module fmt;\n\nimport std;\n\n#define FMT_EXPORT export\n#define FMT_BEGIN_EXPORT export {\n#define FMT_END_EXPORT }\n\n// If you define FMT_ATTACH_TO_GLOBAL_MODULE\n// - all declarations are detached from module 'fmt'\n// - the module behaves like a traditional static library, too\n// - all library symbols are mangled traditionally\n// - you can mix TUs with either importing or #including the {fmt} API\n#ifdef FMT_ATTACH_TO_GLOBAL_MODULE\nextern \"C++\" {\n#endif\n\n#ifndef FMT_OS\n# define FMT_OS 1\n#endif\n\n// All library-provided declarations and definitions must be in the module\n// purview to be exported.\n#include \"fmt/args.h\"\n#include \"fmt/chrono.h\"\n#include \"fmt/color.h\"\n#include \"fmt/compile.h\"\n#include \"fmt/format.h\"\n#if FMT_OS\n# include \"fmt/os.h\"\n#endif\n#include \"fmt/ostream.h\"\n#include \"fmt/printf.h\"\n#include \"fmt/ranges.h\"\n#include \"fmt/std.h\"\n#include \"fmt/xchar.h\"\n\n#ifdef FMT_ATTACH_TO_GLOBAL_MODULE\n}\n#endif\n\n#ifdef FMT_ATTACH_TO_GLOBAL_MODULE\nextern \"C++\" {\n#endif\n\n#if FMT_HAS_INCLUDE(\"format.cc\")\n# include \"format.cc\"\n#endif\n#if FMT_OS && FMT_HAS_INCLUDE(\"os.cc\")\n# include \"os.cc\"\n#endif\n\n#ifdef FMT_ATTACH_TO_GLOBAL_MODULE\n}\n#endif\n",
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},
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sources = { "mcpp_generated/fmt_module.cc" },
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sources = { "mcpp_generated/fmt_module.cppm" },
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targets = { ["fmt"] = { kind = "lib" } },
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deps = { },
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},

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