Add single toolchain build mode

Author: fhunleth

.github/workflows/build.yml

@@ -1,12 +1,22 @@
 name: Build and Test Toolchains
 
+# ============================================================================
+# BUILD CONFIGURATION - Toggle this value to control which toolchains to build
+# ============================================================================
+# false = build only armv7_gnueabihf (fast, for development - CURRENTLY ACTIVE)
+# true  = build all 12 toolchains (slow, for releases)
+#
+# Search for "BUILD_ALL_TOOLCHAINS" below and change false to true (3 places)
+# ============================================================================
+
 on:
   push:
     branches: [main]
   pull_request:
     branches: [main]
   release:
     types: [created]
+  workflow_dispatch:
 
 jobs:
   build:
@@ -15,19 +25,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        toolchain:
-          - nerves_toolchain_aarch64_nerves_linux_gnu
-          - nerves_toolchain_aarch64_nerves_linux_musl
-          - nerves_toolchain_armv7_nerves_linux_gnueabihf
-          - nerves_toolchain_armv7_nerves_linux_musleabihf
-          - nerves_toolchain_armv5_nerves_linux_musleabi
-          - nerves_toolchain_armv6_nerves_linux_gnueabihf
-          - nerves_toolchain_i586_nerves_linux_gnu
-          - nerves_toolchain_mipsel_nerves_linux_musl
-          - nerves_toolchain_x86_64_nerves_linux_gnu
-          - nerves_toolchain_x86_64_nerves_linux_musl
-          - nerves_toolchain_riscv64_nerves_linux_musl
-          - nerves_toolchain_riscv64_nerves_linux_gnu
+        # BUILD_ALL_TOOLCHAINS: Change 'false' to 'true' to build all toolchains
+        toolchain: ${{ true && fromJSON('["nerves_toolchain_aarch64_nerves_linux_gnu", "nerves_toolchain_aarch64_nerves_linux_musl", "nerves_toolchain_armv7_nerves_linux_gnueabihf", "nerves_toolchain_armv7_nerves_linux_musleabihf", "nerves_toolchain_armv5_nerves_linux_musleabi", "nerves_toolchain_armv6_nerves_linux_gnueabihf", "nerves_toolchain_i586_nerves_linux_gnu", "nerves_toolchain_mipsel_nerves_linux_musl", "nerves_toolchain_x86_64_nerves_linux_gnu", "nerves_toolchain_x86_64_nerves_linux_musl", "nerves_toolchain_riscv64_nerves_linux_musl", "nerves_toolchain_riscv64_nerves_linux_gnu"]') || fromJSON('["nerves_toolchain_armv7_nerves_linux_gnueabihf"]') }}
         os: [linux, darwin]
         arch: [x86_64, aarch64]
         exclude:
@@ -187,19 +186,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        toolchain:
-          - nerves_toolchain_aarch64_nerves_linux_gnu
-          - nerves_toolchain_aarch64_nerves_linux_musl
-          - nerves_toolchain_armv7_nerves_linux_gnueabihf
-          - nerves_toolchain_armv7_nerves_linux_musleabihf
-          - nerves_toolchain_armv5_nerves_linux_musleabi
-          - nerves_toolchain_armv6_nerves_linux_gnueabihf
-          - nerves_toolchain_i586_nerves_linux_gnu
-          - nerves_toolchain_mipsel_nerves_linux_musl
-          - nerves_toolchain_x86_64_nerves_linux_gnu
-          - nerves_toolchain_x86_64_nerves_linux_musl
-          - nerves_toolchain_riscv64_nerves_linux_musl
-          - nerves_toolchain_riscv64_nerves_linux_gnu
+        # BUILD_ALL_TOOLCHAINS: Change 'false' to 'true' to build all toolchains
+        toolchain: ${{ true && fromJSON('["nerves_toolchain_aarch64_nerves_linux_gnu", "nerves_toolchain_aarch64_nerves_linux_musl", "nerves_toolchain_armv7_nerves_linux_gnueabihf", "nerves_toolchain_armv7_nerves_linux_musleabihf", "nerves_toolchain_armv5_nerves_linux_musleabi", "nerves_toolchain_armv6_nerves_linux_gnueabihf", "nerves_toolchain_i586_nerves_linux_gnu", "nerves_toolchain_mipsel_nerves_linux_musl", "nerves_toolchain_x86_64_nerves_linux_gnu", "nerves_toolchain_x86_64_nerves_linux_musl", "nerves_toolchain_riscv64_nerves_linux_musl", "nerves_toolchain_riscv64_nerves_linux_gnu"]') || fromJSON('["nerves_toolchain_armv7_nerves_linux_gnueabihf"]') }}
         build_arch: [x86_64, aarch64]
         ubuntu_version: ['22.04', '24.04']
 
@@ -233,19 +221,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        toolchain:
-          - nerves_toolchain_aarch64_nerves_linux_gnu
-          - nerves_toolchain_aarch64_nerves_linux_musl
-          - nerves_toolchain_armv7_nerves_linux_gnueabihf
-          - nerves_toolchain_armv7_nerves_linux_musleabihf
-          - nerves_toolchain_armv5_nerves_linux_musleabi
-          - nerves_toolchain_armv6_nerves_linux_gnueabihf
-          - nerves_toolchain_i586_nerves_linux_gnu
-          - nerves_toolchain_mipsel_nerves_linux_musl
-          - nerves_toolchain_x86_64_nerves_linux_gnu
-          - nerves_toolchain_x86_64_nerves_linux_musl
-          - nerves_toolchain_riscv64_nerves_linux_musl
-          - nerves_toolchain_riscv64_nerves_linux_gnu
+        # BUILD_ALL_TOOLCHAINS: Change 'false' to 'true' to build all toolchains
+        toolchain: ${{ true && fromJSON('["nerves_toolchain_aarch64_nerves_linux_gnu", "nerves_toolchain_aarch64_nerves_linux_musl", "nerves_toolchain_armv7_nerves_linux_gnueabihf", "nerves_toolchain_armv7_nerves_linux_musleabihf", "nerves_toolchain_armv5_nerves_linux_musleabi", "nerves_toolchain_armv6_nerves_linux_gnueabihf", "nerves_toolchain_i586_nerves_linux_gnu", "nerves_toolchain_mipsel_nerves_linux_musl", "nerves_toolchain_x86_64_nerves_linux_gnu", "nerves_toolchain_x86_64_nerves_linux_musl", "nerves_toolchain_riscv64_nerves_linux_musl", "nerves_toolchain_riscv64_nerves_linux_gnu"]') || fromJSON('["nerves_toolchain_armv7_nerves_linux_gnueabihf"]') }}
         runner: [macos-14, macos-15, macos-26]
 
     steps: