Fix: AOT link memcpy.1 undefined — duplicate decl peers of #31894 (#31910)

lib/JIT/Builtin/GcCollectCyclesRuntime.php

@@ -929,24 +929,7 @@ private static function ensureExternals(Context $context): void
 
     private static function ensureExternal(Context $context, string $name, $ft): void
     {
-        try {
-            $context->lookupFunction($name);
-
-            return;
-        } catch (\Throwable $e) {
-        }
-        // The symbol may already exist in the MODULE while being absent from the context registry —
-        // LibcExtern adds `memset` and gives it a body via implementMemsetBody() without every
-        // caller having registered it. addFunction() on an existing name does not fail; LLVM
-        // silently renames the second one to `memset.1`, which carries no body, so the link ends
-        // with `undefined reference to memset.1` from phpc_gc_collect_cycles_impl and EVERY AOT
-        // binary fails to link (aot-smoke 0/8). Reuse the existing declaration instead, matching
-        // the getNamedFunction()-first pattern LibcExtern already uses.
-        $fn = $context->module->getNamedFunction($name);
-        if (null === $fn) {
-            $fn = $context->module->addFunction($name, $ft);
-        }
-        $context->registerFunction($name, $fn);
+        \PHPCompiler\JIT\LibcExtern::ensureExternalDecl($context, $name, $ft);
     }
 
     private static function registerLinkedRuntime(Context $context): void

lib/JIT/Builtin/ObStorageLlvm.php

@@ -7,6 +7,7 @@
 use PHPCompiler\ext\standard\ob_end_clean;
 use PHPCompiler\ext\standard\ob_end_flush;
 use PHPCompiler\JIT\Context;
+use PHPCompiler\JIT\LibcExtern;
 use PHPCompiler\VM\ObStackLimits;
 use PHPLLVM\Builder;
 use PHPLLVM\Value;
@@ -1130,7 +1131,7 @@ private static function ensureLibc(Context $context): void
         self::ensureExternal($context, 'strlen', $context->context->functionType($sizeT, false, $i8p));
         self::ensureExternal($context, 'write', $context->context->functionType($i64, false, $i32, $i8p, $i64));
         self::ensureExternal($context, 'fflush', $context->context->functionType($i32, false, $i8p));
-        self::ensureExternal($context, 'memcpy', $context->context->functionType($i8p, false, $i8p, $i8p, $sizeT));
+        LibcExtern::ensureMemcpyDecl($context);
         self::ensureExternal($context, 'malloc', $context->context->functionType($i8p, false, $sizeT));
         self::ensureExternal(
             $context,
@@ -1185,12 +1186,7 @@ private static function fn(Context $context, string $name, $ret, bool $vararg, .
 
     private static function ensureExternal(Context $context, string $name, $ft): void
     {
-        try {
-            $context->lookupFunction($name);
-        } catch (\Throwable) {
-            $fn = $context->module->addFunction($name, $ft);
-            $context->registerFunction($name, $fn);
-        }
+        LibcExtern::ensureExternalDecl($context, $name, $ft);
     }
 
     private static function registerLinkedRuntime(Context $context, bool $requireAll = true): void

lib/JIT/Builtin/OutputRewriteVarsStorage.php

@@ -73,8 +73,8 @@ public static function ensureLibc(Context $context): void
     {
         $i8p = $context->getTypeFromString('int8*');
         $sizeT = $context->getTypeFromString('size_t');
-        self::ensureExternal($context, 'memcpy', $context->context->functionType($i8p, false, $i8p, $i8p, $sizeT));
-        self::ensureExternal($context, 'malloc', $context->context->functionType($i8p, false, $sizeT));
+        \PHPCompiler\JIT\LibcExtern::ensureMemcpyDecl($context);
+        \PHPCompiler\JIT\LibcExtern::ensureExternalDecl($context, 'malloc', $context->context->functionType($i8p, false, $sizeT));
     }
 
     /** Append name\\x1Evalue (with \\x1D separator when blob non-empty). */
@@ -391,11 +391,6 @@ private static function lenPtr(Context $context, string $name): Value
 
     private static function ensureExternal(Context $context, string $name, $ft): void
     {
-        try {
-            $context->lookupFunction($name);
-        } catch (\Throwable) {
-            $fn = $context->module->addFunction($name, $ft);
-            $context->registerFunction($name, $fn);
-        }
+        \PHPCompiler\JIT\LibcExtern::ensureExternalDecl($context, $name, $ft);
     }
 }

lib/JIT/Builtin/StringSscanfByRef.php

@@ -155,19 +155,8 @@ private static function ensureJitHelperCompiled(Context $context): void
 
     private static function ensureRuntimeHelpers(Context $context): void
     {
-        // Match LibcExtern i8* memcpy — void* decls make NestedJIT emit mistyped calls (#27663).
         \PHPCompiler\JIT\LibcExtern::register($context);
-        try {
-            $context->lookupFunction('memcpy');
-        } catch (\Throwable) {
-            $i8p = $context->getTypeFromString('int8*');
-            $sizeT = $context->getTypeFromString('size_t');
-            $fn = $context->module->addFunction(
-                'memcpy',
-                $context->context->functionType($i8p, false, $i8p, $i8p, $sizeT)
-            );
-            $context->registerFunction('memcpy', $fn);
-        }
+        \PHPCompiler\JIT\LibcExtern::ensureMemcpyDecl($context);
     }
 
     private static function registerLinkedRuntime(Context $context): void

lib/JIT/Builtin/StringZlibJit.php

@@ -175,12 +175,7 @@ private static function ensureRuntimeHelpers(Context $context): void
 
     private static function ensureExternal(Context $context, string $name, $ft): void
     {
-        try {
-            $context->lookupFunction($name);
-        } catch (\Throwable) {
-            $fn = $context->module->addFunction($name, $ft);
-            $context->registerFunction($name, $fn);
-        }
+        \PHPCompiler\JIT\LibcExtern::ensureExternalDecl($context, $name, $ft);
     }
 
     private static function emitDeflateBytes(Context $context): void

lib/JIT/Builtin/UrlRewriterApplyRuntime.php

@@ -237,14 +237,9 @@ private static function ensureStringInit(Context $context): void
         foreach ([
             '__string__init' => $context->context->functionType($strPtr, false, $i64, $i8p),
             'malloc' => $context->context->functionType($i8p, false, $sizeT),
-            'memcpy' => $context->context->functionType($i8p, false, $i8p, $i8p, $sizeT),
         ] as $name => $ft) {
-            try {
-                $context->lookupFunction($name);
-            } catch (\Throwable) {
-                $fn = $context->module->addFunction($name, $ft);
-                $context->registerFunction($name, $fn);
-            }
+            \PHPCompiler\JIT\LibcExtern::ensureExternalDecl($context, $name, $ft);
         }
+        \PHPCompiler\JIT\LibcExtern::ensureMemcpyDecl($context);
     }
 }

lib/JIT/LibcExtern.php

@@ -654,18 +654,30 @@ private static function implementStrcmpBody(Context $context): void
         $context->registerFunction('strcmp', $fn);
     }
 
-    private static function ensure(Context $context, string $name, $fnType): void
+    /**
+     * Declare an external libc/helper symbol without versioning duplicates (#31894).
+     *
+     * lookupFunction() may throw while the symbol already exists in the MODULE (LibcExtern
+     * implement*Body adds bodies without always registering). addFunction() on an existing name
+     * silently versions to name.N with no body → link failure for every AOT binary.
+     */
+    public static function ensureExternalDecl(Context $context, string $name, $fnType): void
     {
-        if (null !== $context->module->getNamedFunction($name)) {
-            return;
-        }
         try {
             $context->lookupFunction($name);
 
             return;
         } catch (\Throwable) {
         }
-        $fn = $context->module->addFunction($name, $fnType);
+        $fn = $context->module->getNamedFunction($name);
+        if (null === $fn) {
+            $fn = $context->module->addFunction($name, $fnType);
+        }
         $context->registerFunction($name, $fn);
     }
+
+    private static function ensure(Context $context, string $name, $fnType): void
+    {
+        self::ensureExternalDecl($context, $name, $fnType);
+    }
 }