libgomp support instead of custom built gcc toolchain?

config/lib.json

@@ -148,6 +148,17 @@
             "IOKit"
         ]
     },
+    "libgomp": {
+        "source": "gcc",
+        "static-libs-linux": [
+            "libgomp.a"
+        ],
+        "headers": [
+            "omp.h",
+            "openacc.h",
+            "acc_prof.h"
+        ]
+    },
     "gmp": {
         "source": "gmp",
         "static-libs-unix": [
@@ -213,6 +224,9 @@
             "libheif",
             "bzip2"
         ],
+        "lib-depends-linux": [
+            "libgomp"
+        ],
         "lib-suggests": [
             "zstd",
             "xz",

config/source.json

@@ -249,6 +249,13 @@
             "path": "LICENSE.TXT"
         }
     },
+    "gcc": {
+        "type": "custom",
+        "license": {
+            "type": "file",
+            "path": "COPYING"
+        }
+    },
     "gettext": {
         "type": "filelist",
         "url": "https://ftp.gnu.org/pub/gnu/gettext/",

src/SPC/builder/extension/imagick.php

@@ -12,18 +12,17 @@ class imagick extends Extension
 {
     public function patchBeforeMake(): bool
     {
-        if (getenv('SPC_LIBC') !== 'musl') {
+        if (PHP_OS_FAMILY !== 'Linux') {
             return false;
         }
-        // imagick with calls omp_pause_all which requires -lgomp, on non-musl we build imagick without openmp
+        // imagemagick with --enable-openmp calls omp_pause_all which requires -lgomp on Linux
         $extra_libs = trim(getenv('SPC_EXTRA_LIBS') . ' -lgomp');
         f_putenv('SPC_EXTRA_LIBS=' . $extra_libs);
         return true;
     }
 
     public function getUnixConfigureArg(bool $shared = false): string
     {
-        $disable_omp = getenv('SPC_LIBC') === 'musl' ? '' : ' ac_cv_func_omp_pause_resource_all=no';
-        return '--with-imagick=' . BUILD_ROOT_PATH . $disable_omp;
+        return '--with-imagick=' . BUILD_ROOT_PATH;
     }
 }

src/SPC/builder/linux/library/libgomp.php

@@ -0,0 +1,60 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SPC\builder\linux\library;
+
+use SPC\builder\linux\LinuxBuilder;
+use SPC\exception\FileSystemException;
+use SPC\exception\RuntimeException;
+use SPC\store\FileSystem;
+use SPC\store\source\GccSource;
+
+class libgomp extends LinuxLibraryBase
+{
+    public const NAME = 'libgomp';
+
+    protected array $static_libs = ['libgomp.a'];
+
+    protected array $headers = [
+        'omp.h',
+        'openacc.h',
+        'acc_prof.h',
+    ];
+
+    public function __construct(LinuxBuilder $builder)
+    {
+        parent::__construct($builder);
+        $this->source_dir = SOURCE_PATH . '/gcc';
+    }
+
+    /**
+     * @throws RuntimeException
+     * @throws FileSystemException
+     */
+    protected function build(): void
+    {
+        if (getenv('SPC_LIBC') !== 'glibc') {
+            return; // can use musl's libgomp.a as it's built with -fPIC
+        }
+        $outdir = $this->source_dir . '/libgomp/build/out';
+
+        FileSystem::createDir($this->source_dir . '/libgomp/build');
+        shell()->cd($this->source_dir . '/libgomp/build')
+            ->setEnv([
+                'CFLAGS' => $this->getLibExtraCFlags(),
+                'LDFLAGS' => $this->getLibExtraLdFlags(),
+                'LIBS' => $this->getLibExtraLibs(),
+            ])
+            ->execWithEnv('../configure --enable-static --disable-shared --prefix= --disable-multilib --with-pic --libdir=/lib --includedir=/include')
+            ->execWithEnv('make clean')
+            ->execWithEnv("make -j{$this->builder->concurrency}")
+            ->execWithEnv("make install DESTDIR={$outdir}");
+
+        copy($outdir . '/lib64/libgomp.a', BUILD_LIB_PATH . '/libgomp.a');
+        FileSystem::copyDir(
+            $outdir . '/lib/gcc/' . GccSource::getGccVersion() . '/include',
+            BUILD_ROOT_PATH
+        );
+    }
+}

src/SPC/builder/unix/library/imagemagick.php

@@ -18,9 +18,7 @@ trait imagemagick
      */
     protected function build(): void
     {
-        // TODO: glibc rh 10 toolset's libgomp.a was built without -fPIC -fPIE so we can't use openmp without depending on libgomp.so
-        $openmp = getenv('SPC_LIBC') === 'musl' ? '--enable-openmp' : '--disable-openmp';
-        $extra = "--without-jxl --without-x {$openmp} ";
+        $extra = '--without-jxl --without-x --enable-openmp ';
         $required_libs = '';
         $optional_libs = [
             'libzip' => 'zip',

src/SPC/store/source/GccSource.php

@@ -0,0 +1,69 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SPC\store\source;
+
+use JetBrains\PhpStorm\ArrayShape;
+use SPC\exception\DownloaderException;
+use SPC\exception\FileSystemException;
+use SPC\store\Downloader;
+
+class GccSource extends CustomSourceBase
+{
+    public const NAME = 'gcc';
+
+    /**
+     * @throws DownloaderException
+     * @throws FileSystemException
+     */
+    public function fetch(bool $force = false, ?array $config = null, int $lock_as = SPC_DOWNLOAD_SOURCE): void
+    {
+        $version = self::getGccVersion();
+        Downloader::downloadSource('gcc', self::getGccSourceInfo($version), $force);
+    }
+
+    /**
+     * Get the installed GCC version
+     *
+     * @return string              The GCC version (e.g., "11.5.0")
+     * @throws DownloaderException
+     */
+    public static function getGccVersion(): string
+    {
+        $cc = getenv('CC') ?: 'gcc';
+        $output = [];
+        $return_var = 0;
+
+        exec("{$cc} --version", $output, $return_var);
+
+        if ($return_var !== 0 || empty($output)) {
+            throw new DownloaderException("Failed to get GCC version using {$cc}");
+        }
+
+        // Parse the version from the output
+        // Example output: "gcc (GCC) 11.5.0" or "gcc (Ubuntu 4.8.5-4ubuntu2) 4.8.5"
+        $version_line = $output[0];
+        if (preg_match('/\s(\d+\.\d+\.\d+)/', $version_line, $matches)) {
+            // official ftp mirrors only keep .0 releases
+            return preg_replace('/\.\d+$/', '.0', $matches[1]);
+        }
+
+        throw new DownloaderException("Could not parse GCC version from: {$version_line}");
+    }
+
+    /**
+     * Get the GCC source information for a specific version
+     *
+     * @param  string $version The GCC version to download
+     * @return array  The source information
+     */
+    #[ArrayShape(['type' => 'string', 'url' => 'string'])]
+    public static function getGccSourceInfo(string $version): array
+    {
+        return [
+            'type' => 'url',
+            'url' => "https://ftp.gnu.org/gnu/gcc/gcc-{$version}/gcc-{$version}.tar.xz",
+        ];
+    }
+}

src/SPC/util/SPCConfigUtil.php

@@ -116,7 +116,7 @@ private function getLibsString(array $libraries): string
             }
         }
         // patch: imagick (imagemagick wrapper) for linux needs libgomp
-        if (in_array('imagemagick', $libraries) && PHP_OS_FAMILY === 'Linux' && getenv('SPC_LIBC') === 'musl') {
+        if (in_array('imagemagick', $libraries) && PHP_OS_FAMILY === 'Linux') {
             $short_name[] = '-lgomp';
         }
         return implode(' ', $short_name);