atomvm · petermm · Mar 8, 2026
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -4,6 +4,13 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.7.0-alpha.1] - Unreleased
+
+### Added
+### Changed
+### Fixed
+- `erlang:system_info(system_architecture)` now reports normalized `arch-vendor-os` strings
+
 ## [0.7.0-alpha.0] - 2026-03-20
 
 ### Added

diff --git a/CMakeModules/SystemArchitecture.cmake b/CMakeModules/SystemArchitecture.cmake
@@ -0,0 +1,71 @@
+#
+# This file is part of AtomVM.
+#
+# Copyright 2026 Peter M. <petermm@gmail.com>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# SPDX-License-Identifier: Apache-2.0 OR LGPL-2.1-or-later
+#
+
+function(avm_get_system_architecture_string out_var)
+    set(options)
+    set(one_value_args PLATFORM_VENDOR PLATFORM_OS)
+    cmake_parse_arguments(PARSE_ARGV 1 AVM "${options}" "${one_value_args}" "")
+
+    execute_process(
+        COMMAND ${CMAKE_C_COMPILER} -dumpmachine
+        OUTPUT_VARIABLE avm_raw_system_architecture
+        OUTPUT_STRIP_TRAILING_WHITESPACE
+        ERROR_QUIET
+    )
+
+    if (avm_raw_system_architecture STREQUAL "")
+        unset(${out_var} PARENT_SCOPE)
+        return()
+    endif()
+
+    string(REPLACE "-" ";" avm_system_architecture_parts "${avm_raw_system_architecture}")
+    list(LENGTH avm_system_architecture_parts avm_system_architecture_length)
+
+    if (avm_system_architecture_length EQUAL 1)
+        list(GET avm_system_architecture_parts 0 avm_architecture)
+        if (DEFINED AVM_PLATFORM_VENDOR)
+            set(avm_vendor "${AVM_PLATFORM_VENDOR}")
+        else()
+            set(avm_vendor "unknown")
+        endif()
+        set(avm_os "unknown")
+    elseif (avm_system_architecture_length EQUAL 2)
+        list(GET avm_system_architecture_parts 0 avm_architecture)
+        if (DEFINED AVM_PLATFORM_VENDOR)
+            set(avm_vendor "${AVM_PLATFORM_VENDOR}")
+        else()
+            set(avm_vendor "unknown")
+        endif()
+        list(GET avm_system_architecture_parts 1 avm_os)
+    else()
+        list(GET avm_system_architecture_parts 0 avm_architecture)
+        list(GET avm_system_architecture_parts 1 avm_vendor)
+        if (DEFINED AVM_PLATFORM_VENDOR AND (avm_vendor STREQUAL "none" OR avm_vendor STREQUAL "unknown"))
+            set(avm_vendor "${AVM_PLATFORM_VENDOR}")
+        endif()
+
+        list(REMOVE_AT avm_system_architecture_parts 0 1)
+        string(REPLACE ";" "_" avm_os "${avm_system_architecture_parts}")
+    endif()
+
+    if (DEFINED AVM_PLATFORM_OS)
+        set(avm_os "${AVM_PLATFORM_OS}")
+    endif()
+
+    string(REPLACE "-" "_" avm_architecture "${avm_architecture}")
+    string(REPLACE "-" "_" avm_vendor "${avm_vendor}")
+    string(REPLACE "-" "_" avm_os "${avm_os}")
+
+    set(${out_var} "${avm_architecture}-${avm_vendor}-${avm_os}" PARENT_SCOPE)
+endfunction()
diff --git a/src/libAtomVM/CMakeLists.txt b/src/libAtomVM/CMakeLists.txt
@@ -319,6 +319,26 @@ else()
     set(ATOMVM_VERSION ${ATOMVM_BASE_VERSION})
 endif()
 
+set(AVM_SYSTEM_ARCHITECTURE_FALLBACK_ARCH "${CMAKE_SYSTEM_PROCESSOR}")
+if (AVM_SYSTEM_ARCHITECTURE_FALLBACK_ARCH STREQUAL "")
+    set(AVM_SYSTEM_ARCHITECTURE_FALLBACK_ARCH "unknown")
+endif()
+string(REPLACE "-" "_" AVM_SYSTEM_ARCHITECTURE_FALLBACK_ARCH "${AVM_SYSTEM_ARCHITECTURE_FALLBACK_ARCH}")
+
+set(AVM_SYSTEM_ARCHITECTURE_FALLBACK_OS "${CMAKE_SYSTEM_NAME}")
+if (AVM_SYSTEM_ARCHITECTURE_FALLBACK_OS STREQUAL "")
+    set(AVM_SYSTEM_ARCHITECTURE_FALLBACK_OS "unknown")
+endif()
+if (NOT CMAKE_SYSTEM_VERSION STREQUAL "")
+    string(APPEND AVM_SYSTEM_ARCHITECTURE_FALLBACK_OS "_${CMAKE_SYSTEM_VERSION}")
+endif()
+string(REPLACE "-" "_" AVM_SYSTEM_ARCHITECTURE_FALLBACK_OS "${AVM_SYSTEM_ARCHITECTURE_FALLBACK_OS}")
+
+if (NOT DEFINED AVM_SYSTEM_ARCHITECTURE_STRING OR AVM_SYSTEM_ARCHITECTURE_STRING STREQUAL "")
+    set(AVM_SYSTEM_ARCHITECTURE_STRING
+        "${AVM_SYSTEM_ARCHITECTURE_FALLBACK_ARCH}-unknown-${AVM_SYSTEM_ARCHITECTURE_FALLBACK_OS}")
+endif()
+
 # Add include to directory where avm_version.h is generated so targets linking
 # libAtomVM can access it
 target_include_directories(libAtomVM PUBLIC ${CMAKE_CURRENT_BINARY_DIR})

diff --git a/src/libAtomVM/nifs.c b/src/libAtomVM/nifs.c
@@ -3173,13 +3173,11 @@ static term nif_erlang_system_info(Context *ctx, int argc, term argv[])
         return term_from_int11(sizeof(avm_float_t));
     }
     if (key == SYSTEM_ARCHITECTURE_ATOM) {
-        char buf[128];
-        snprintf(buf, 128, "%s-%s-%s", SYSTEM_NAME, SYSTEM_VERSION, SYSTEM_ARCHITECTURE);
-        size_t len = strnlen(buf, 128);
+        size_t len = sizeof(SYSTEM_ARCHITECTURE_STRING) - 1;
         if (memory_ensure_free_opt(ctx, term_binary_heap_size(len), MEMORY_CAN_SHRINK) != MEMORY_GC_OK) {
             RAISE_ERROR(OUT_OF_MEMORY_ATOM);
         }
-        return term_from_literal_binary((const uint8_t *) buf, len, &ctx->heap, ctx->global);
+        return term_from_literal_binary((const uint8_t *) SYSTEM_ARCHITECTURE_STRING, len, &ctx->heap, ctx->global);
     }
     if (key == ATOMVM_VERSION_ATOM) {
         size_t len = strlen(ATOMVM_VERSION);

diff --git a/src/libAtomVM/version.h.in b/src/libAtomVM/version.h.in
@@ -21,4 +21,5 @@
 #define SYSTEM_NAME "${CMAKE_SYSTEM_NAME}"
 #define SYSTEM_VERSION "${CMAKE_SYSTEM_VERSION}"
 #define SYSTEM_ARCHITECTURE "${CMAKE_SYSTEM_PROCESSOR}"
+#define SYSTEM_ARCHITECTURE_STRING "${AVM_SYSTEM_ARCHITECTURE_STRING}"
 #define ATOMVM_VERSION "${ATOMVM_VERSION}"
diff --git a/src/platforms/emscripten/src/CMakeLists.txt b/src/platforms/emscripten/src/CMakeLists.txt
@@ -24,6 +24,9 @@ add_executable(AtomVM main.c)
 
 target_compile_features(AtomVM PUBLIC c_std_11)
 
+include(SystemArchitecture)
+avm_get_system_architecture_string(AVM_SYSTEM_ARCHITECTURE_STRING)
+
 add_subdirectory(../../../libAtomVM libAtomVM)
 target_link_libraries(AtomVM PUBLIC libAtomVM)
 target_compile_options(libAtomVM PUBLIC -O3 -fno-exceptions -fno-rtti -pthread -sINLINING_LIMIT -sUSE_ZLIB=1)

diff --git a/src/platforms/esp32/components/libatomvm/CMakeLists.txt b/src/platforms/esp32/components/libatomvm/CMakeLists.txt
@@ -29,6 +29,9 @@ idf_component_register(INCLUDE_DIRS "${CMAKE_CURRENT_SOURCE_DIR}/../../../../lib
 # "pedantic" flag should be disabled rather poluting diagnostics with warnings caused from 3rd party
 option(AVM_PEDANTIC_WARNINGS "Pedantic compiler warnings" OFF)
 
+include(SystemArchitecture)
+avm_get_system_architecture_string(AVM_SYSTEM_ARCHITECTURE_STRING PLATFORM_OS esp_idf)
+
 add_subdirectory("${CMAKE_CURRENT_SOURCE_DIR}/../../../../libAtomVM" "libAtomVM")
 
 # Add directory with platform_atomic.h if we mean to use it

diff --git a/src/platforms/esp32/test/main/test_erl_sources/CMakeLists.txt b/src/platforms/esp32/test/main/test_erl_sources/CMakeLists.txt
@@ -74,6 +74,7 @@ compile_erlang(test_rtc_slow)
 compile_erlang(test_select)
 compile_erlang(test_socket)
 compile_erlang(test_ssl)
+compile_erlang(test_system_architecture)
 compile_erlang(test_time_and_processes)
 compile_erlang(test_twdt)
 compile_erlang(test_tz)
@@ -96,6 +97,7 @@ set(erlang_test_beams
     test_select.beam
     test_socket.beam
     test_ssl.beam
+    test_system_architecture.beam
     test_time_and_processes.beam
     test_twdt.beam
     test_tz.beam

diff --git a/src/platforms/esp32/test/main/test_erl_sources/test_system_architecture.erl b/src/platforms/esp32/test/main/test_erl_sources/test_system_architecture.erl
@@ -0,0 +1,34 @@
+%
+% This file is part of AtomVM.
+%
+% Copyright 2026 Peter M. <petermm@gmail.com>
+%
+% Licensed under the Apache License, Version 2.0 (the "License");
+% you may not use this file except in compliance with the License.
+% You may obtain a copy of the License at
+%
+%    http://www.apache.org/licenses/LICENSE-2.0
+%
+% Unless required by applicable law or agreed to in writing, software
+% distributed under the License is distributed on an "AS IS" BASIS,
+% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+% See the License for the specific language governing permissions and
+% limitations under the License.
+%
+% SPDX-License-Identifier: Apache-2.0 OR LGPL-2.1-or-later
+%
+
+-module(test_system_architecture).
+-export([start/0]).
+
+start() ->
+    SystemArchitecture = erlang:system_info(system_architecture),
+    ok =
+        case SystemArchitecture of
+            <<"xtensa-esp-esp_idf">> ->
+                ok;
+            <<"riscv32-esp-esp_idf">> ->
+                ok
+        end,
+    nomatch = binary:match(SystemArchitecture, <<"esp_idf-">>),
+    ok.
diff --git a/src/platforms/esp32/test/main/test_main.c b/src/platforms/esp32/test/main/test_main.c
@@ -502,6 +502,12 @@ TEST_CASE("test_time_and_processes", "[test_run]")
     TEST_ASSERT(term_to_int(ret_value) == 6);
 }
 
+TEST_CASE("test_system_architecture", "[test_run]")
+{
+    term ret_value = avm_test_case("test_system_architecture.beam");
+    TEST_ASSERT(ret_value == OK_ATOM);
+}
+
 TEST_CASE("test_tz", "[test_run]")
 {
     term ret_value = avm_test_case("test_tz.beam");

diff --git a/src/platforms/generic_unix/CMakeLists.txt b/src/platforms/generic_unix/CMakeLists.txt
@@ -45,6 +45,11 @@ endif()
 add_subdirectory(lib)
 target_include_directories(AtomVM PUBLIC lib/)
 
+include(SystemArchitecture)
+if (NOT DEFINED AVM_SYSTEM_ARCHITECTURE_STRING OR "${AVM_SYSTEM_ARCHITECTURE_STRING}" STREQUAL "")
+    avm_get_system_architecture_string(AVM_SYSTEM_ARCHITECTURE_STRING)
+endif()
+
 add_subdirectory(../../libAtomVM libAtomVM)
 target_link_libraries(AtomVM PRIVATE libAtomVM)
 

diff --git a/src/platforms/rp2/src/CMakeLists.txt b/src/platforms/rp2/src/CMakeLists.txt
@@ -34,6 +34,8 @@ set(HAVE_PLATFORM_SMP_H ON)
 if(PICO_RP2040)
 set(HAVE_PLATFORM_ATOMIC_H ON)
 endif()
+include(SystemArchitecture)
+avm_get_system_architecture_string(AVM_SYSTEM_ARCHITECTURE_STRING PLATFORM_VENDOR rp2 PLATFORM_OS none)
 add_subdirectory(../../../libAtomVM libAtomVM)
 target_link_libraries(AtomVM PUBLIC libAtomVM)
 # Also add lib where platform_smp.h and platform_atomic headers are

diff --git a/src/platforms/stm32/src/CMakeLists.txt b/src/platforms/stm32/src/CMakeLists.txt
@@ -105,6 +105,8 @@ target_include_directories(${PROJECT_EXECUTABLE} PUBLIC
 add_dependencies(${PROJECT_EXECUTABLE} picolibc)
 
 # Link libAtomVM
+include(SystemArchitecture)
+avm_get_system_architecture_string(AVM_SYSTEM_ARCHITECTURE_STRING PLATFORM_VENDOR stm32 PLATFORM_OS none)
 add_subdirectory(../../../libAtomVM libAtomVM)
 add_dependencies(libAtomVM picolibc)
 target_link_libraries(${PROJECT_EXECUTABLE} PUBLIC libAtomVM)

diff --git a/tests/erlang_tests/test_system_info.erl b/tests/erlang_tests/test_system_info.erl
@@ -33,7 +33,10 @@ start() ->
             % beam returns a list and probably so should AtomVM.
             assert(is_list(erlang:system_info(system_architecture)));
         _ ->
-            assert(is_binary(erlang:system_info(system_architecture)))
+            SystemArchitecture = erlang:system_info(system_architecture),
+            assert(is_binary(SystemArchitecture)),
+            2 = count_hyphens(SystemArchitecture),
+            false = starts_with_known_os(SystemArchitecture)
     end,
     SystemVersion = erlang:system_info(system_version),
     true = is_list(SystemVersion),
@@ -74,6 +77,16 @@ loop(Pid) ->
 
 assert(true) -> ok.
 
+count_hyphens(<<>>) -> 0;
+count_hyphens(<<"-", Rest/binary>>) -> 1 + count_hyphens(Rest);
+count_hyphens(<<_, Rest/binary>>) -> count_hyphens(Rest).
+
+starts_with_known_os(<<"Darwin-", _/binary>>) -> true;
+starts_with_known_os(<<"Linux-", _/binary>>) -> true;
+starts_with_known_os(<<"FreeBSD-", _/binary>>) -> true;
+starts_with_known_os(<<"DragonFly-", _/binary>>) -> true;
+starts_with_known_os(_) -> false.
+
 test_port_count("BEAM") ->
     N = erlang:system_info(port_count),
     true = is_integer(N),