From 5ec87b2ba7cb6643572cc02db83aaa4d3eaaa700 Mon Sep 17 00:00:00 2001
From: Brad King <brad.king@kitware.com>
Date: Tue, 25 Nov 2025 14:13:20 -0500
Subject: [PATCH] Emscripten: Provide CMAKE_<LANG>_COMPILER_ARCHITECTURE_ID

Extend commit 96d9b94a98 (Emscripten: Add platform modules, 2025-05-16,
v4.2.0-rc1~607^2~3) to account for commit 7f0f382c55 (Provide
CMAKE_<LANG>_COMPILER_ARCHITECTURE_ID on more compilers, 2025-03-24,
v4.1.0-rc1~499^2).

Fixes: #27425
---
 Help/variable/CMAKE_LANG_COMPILER_ARCHITECTURE_ID.rst   | 6 ++++++
 Modules/CMakeCompilerABI.h                              | 4 ++++
 Modules/CMakeFortranCompilerABI.F                       | 4 ++++
 Modules/CMakeFortranCompilerABI.F90                     | 4 ++++
 Modules/Internal/CMakeParseCompilerArchitectureId.cmake | 4 ++++
 Tests/RunCMake/Emscripten/C-enable-stdout.txt           | 1 +
 Tests/RunCMake/Emscripten/C-enable.cmake                | 1 +
 7 files changed, 24 insertions(+)

diff --git a/Help/variable/CMAKE_LANG_COMPILER_ARCHITECTURE_ID.rst b/Help/variable/CMAKE_LANG_COMPILER_ARCHITECTURE_ID.rst
index ff54da29c4..c6853e3654 100644
--- a/Help/variable/CMAKE_LANG_COMPILER_ARCHITECTURE_ID.rst
+++ b/Help/variable/CMAKE_LANG_COMPILER_ARCHITECTURE_ID.rst
@@ -126,6 +126,12 @@ targets a UNIX platform.
 ``sw_64``
   Sunway
 
+``wasm32``
+  WebAssembly (Emscripten) 32-bit
+
+``wasm64``
+  WebAssembly (Emscripten) 64-bit
+
 ``x86_64``
   Intel 64-bit
 
diff --git a/Modules/CMakeCompilerABI.h b/Modules/CMakeCompilerABI.h
index 40c5be4b3a..bd90ea241c 100644
--- a/Modules/CMakeCompilerABI.h
+++ b/Modules/CMakeCompilerABI.h
@@ -144,6 +144,10 @@ static unsigned short const info_byte_order_little_endian[] = {
 #  else
 #    define ARCHITECTURE_ID "ppc"
 #  endif
+#elif defined(__wasm64) || defined(__wasm64__)
+#  define ARCHITECTURE_ID "wasm64"
+#elif defined(__wasm32) || defined(__wasm32__)
+#  define ARCHITECTURE_ID "wasm32"
 #endif
 
 /* Construct the string literal in pieces to prevent the source from
diff --git a/Modules/CMakeFortranCompilerABI.F b/Modules/CMakeFortranCompilerABI.F
index e9e05528e6..ed827305e2 100644
--- a/Modules/CMakeFortranCompilerABI.F
+++ b/Modules/CMakeFortranCompilerABI.F
@@ -143,6 +143,10 @@
 #  else
         PRINT *, 'INFO:arch[ppc]'
 #  endif
+#elif defined(__wasm64) || defined(__wasm64__)
+        PRINT *, 'INFO:arch[wasm64]'
+#elif defined(__wasm32) || defined(__wasm32__)
+        PRINT *, 'INFO:arch[wasm32]'
 #endif
 
         PRINT *, 'ABI Detection'
diff --git a/Modules/CMakeFortranCompilerABI.F90 b/Modules/CMakeFortranCompilerABI.F90
index 0246d2a66c..1dfd560961 100644
--- a/Modules/CMakeFortranCompilerABI.F90
+++ b/Modules/CMakeFortranCompilerABI.F90
@@ -151,6 +151,10 @@ PRINT *, 'INFO:arch[ppcle]'
 #  else
 PRINT *, 'INFO:arch[ppc]'
 #  endif
+#elif defined(__wasm64) || defined(__wasm64__)
+PRINT *, 'INFO:arch[wasm64]'
+#elif defined(__wasm32) || defined(__wasm32__)
+PRINT *, 'INFO:arch[wasm32]'
 #endif
 
 PRINT *, 'ABI Detection'
diff --git a/Modules/Internal/CMakeParseCompilerArchitectureId.cmake b/Modules/Internal/CMakeParseCompilerArchitectureId.cmake
index e5ee90e7e5..2f3b9b9ad9 100644
--- a/Modules/Internal/CMakeParseCompilerArchitectureId.cmake
+++ b/Modules/Internal/CMakeParseCompilerArchitectureId.cmake
@@ -69,6 +69,10 @@ function(cmake_parse_compiler_architecture_id triple arch_id_var)
     set(ARCHITECTURE_ID "ppcle")
   elseif(_dumpmachine_triple MATCHES "^(powerpc|ppc)-")
     set(ARCHITECTURE_ID "ppc")
+  elseif(_dumpmachine_triple MATCHES "^wasm64-")
+    set(ARCHITECTURE_ID "wasm64")
+  elseif(_dumpmachine_triple MATCHES "^wasm32-")
+    set(ARCHITECTURE_ID "wasm32")
   else()
     set(ARCHITECTURE_ID "")
   endif()
diff --git a/Tests/RunCMake/Emscripten/C-enable-stdout.txt b/Tests/RunCMake/Emscripten/C-enable-stdout.txt
index c14ab8a3a1..8843cbe738 100644
--- a/Tests/RunCMake/Emscripten/C-enable-stdout.txt
+++ b/Tests/RunCMake/Emscripten/C-enable-stdout.txt
@@ -1,2 +1,3 @@
 -- CMAKE_C_BYTE_ORDER='LITTLE_ENDIAN'
+-- CMAKE_C_COMPILER_ARCHITECTURE_ID='wasm(32|64)'
 -- CMAKE_C_SIZEOF_DATA_PTR='[1-9][0-9]*'
diff --git a/Tests/RunCMake/Emscripten/C-enable.cmake b/Tests/RunCMake/Emscripten/C-enable.cmake
index 7878def517..4fa3e51176 100644
--- a/Tests/RunCMake/Emscripten/C-enable.cmake
+++ b/Tests/RunCMake/Emscripten/C-enable.cmake
@@ -1,6 +1,7 @@
 enable_language(C)
 foreach(var IN ITEMS
     CMAKE_C_BYTE_ORDER
+    CMAKE_C_COMPILER_ARCHITECTURE_ID
     CMAKE_C_SIZEOF_DATA_PTR
   )
   message(STATUS "${var}='${${var}}'")