Port bootstrap build on OpenBSD

eng/native/configurecompiler.cmake

@@ -847,6 +847,27 @@ else(CLR_CMAKE_TARGET_UNIX)
   add_compile_definitions($<$<NOT:$<BOOL:$<TARGET_PROPERTY:IGNORE_DEFAULT_TARGET_OS>>>:TARGET_WINDOWS>)
 endif(CLR_CMAKE_TARGET_UNIX)
 
+# OpenBSD only exposes its libunwind symbols through the LLVM C++ runtime
+# (libc++/libc++abi), so default to those there. An explicit selection via
+# CLR_CMAKE_CXX_STANDARD_LIBRARY/CLR_CMAKE_CXX_ABI_LIBRARY (applied by the cross
+# toolchain file) still takes precedence.
+if(CLR_CMAKE_TARGET_OPENBSD)
+  if(NOT CLR_CMAKE_CXX_STANDARD_LIBRARY)
+    add_compile_options($<$<COMPILE_LANG_AND_ID:CXX,Clang>:--stdlib=libc++>)
+    add_link_options($<$<LINK_LANG_AND_ID:CXX,Clang>:--stdlib=libc++>)
+  endif()
+  if(NOT CLR_CMAKE_CXX_ABI_LIBRARY)
+    add_link_options("LINKER:-lc++abi")
+  endif()
+
+  # Use native (not emulated) TLS so C/C++ __thread vars match the runtime's assembly.
+  add_compile_options(-fno-emulated-tls)
+
+  # OpenBSD has no __tls_get_addr (only static TLS). Use initial-exec so general-dynamic
+  # TLS (and its unresolvable __tls_get_addr reference in shared objects) is never emitted.
+  add_compile_options(-ftls-model=initial-exec)
+endif()
+
 if(CLR_CMAKE_HOST_UNIX_ARM)
    if (NOT DEFINED CLR_ARM_FPU_TYPE)
      set(CLR_ARM_FPU_TYPE vfpv3)

eng/native/functions.cmake

@@ -192,7 +192,13 @@ function(find_unwind_libs UnwindLibs)
     find_library(UNWIND NAMES unwind)
 
     if(UNWIND STREQUAL UNWIND-NOTFOUND)
-      message(FATAL_ERROR "Cannot find libunwind. Try installing libunwind8-dev or libunwind-devel.")
+      if(CLR_CMAKE_TARGET_OPENBSD)
+        # On OpenBSD the libunwind symbols are provided by the C++ ABI library
+        # (libc++abi), so a standalone libunwind is not expected.
+        set(UNWIND "")
+      else()
+        message(FATAL_ERROR "Cannot find libunwind. Try installing libunwind8-dev or libunwind-devel.")
+      endif()
     endif()
 
     set(${UnwindLibs} ${UNWIND_LIBS} ${UNWIND} PARENT_SCOPE)

src/coreclr/gc/unix/gcenv.unix.cpp

@@ -1013,11 +1013,13 @@ static size_t GetCurrentVirtualMemorySize()
 //  non zero if it has succeeded, GetVirtualMemoryMaxAddress() if not available
 size_t GCToOSInterface::GetVirtualMemoryLimit()
 {
+#ifdef RLIMIT_AS
     rlimit addressSpaceLimit;
     if ((getrlimit(RLIMIT_AS, &addressSpaceLimit) == 0) && (addressSpaceLimit.rlim_cur != RLIM_INFINITY))
     {
         return addressSpaceLimit.rlim_cur;
     }
+#endif // RLIMIT_AS
 
     // No virtual memory limit
     return GetVirtualMemoryMaxAddress();

src/coreclr/hosts/corerun/corerun.hpp

@@ -384,6 +384,16 @@ class platform_specific_actions final
 #include <link.h>
 #include <elf.h>
 #include <cstring>
+
+// glibc defines the ElfW() macro to select the native-width Elf type, but some
+// libcs (e.g. OpenBSD) don't provide it. Fall back to the appropriate fixed-width type.
+#ifndef ElfW
+#if defined(TARGET_64BIT)
+#define ElfW(type) Elf64_##type
+#else
+#define ElfW(type) Elf32_##type
+#endif
+#endif // ElfW
 #endif
 
 // CMake generated

src/coreclr/inc/check.h

@@ -1,9 +1,8 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
+
 // ---------------------------------------------------------------------------
 // Check.h
-//
-
 //
 // Assertion checking infrastructure
 // ---------------------------------------------------------------------------
@@ -663,7 +662,7 @@ CHECK CheckAligned(UINT value, UINT alignment);
 CHECK CheckAligned(ULONG value, UINT alignment);
 #endif
 CHECK CheckAligned(UINT64 value, UINT alignment);
-#ifdef __APPLE__
+#if defined(__APPLE__) || defined(__OpenBSD__)
 CHECK CheckAligned(SIZE_T value, UINT alignment);
 #endif
 CHECK CheckAligned(const void *address, UINT alignment);
@@ -673,7 +672,7 @@ CHECK CheckOverflow(UINT value1, UINT value2);
 CHECK CheckOverflow(ULONG value1, ULONG value2);
 #endif
 CHECK CheckOverflow(UINT64 value1, UINT64 value2);
-#ifdef __APPLE__
+#if defined(__APPLE__) || defined(__OpenBSD__)
 CHECK CheckOverflow(SIZE_T value1, SIZE_T value2);
 #endif
 #ifndef __wasm__
@@ -689,15 +688,15 @@ CHECK CheckUnderflow(UINT value1, UINT value2);
 CHECK CheckUnderflow(ULONG value1, ULONG value2);
 #endif
 CHECK CheckUnderflow(UINT64 value1, UINT64 value2);
-#ifdef __APPLE__
+#if defined(__APPLE__) || defined(__OpenBSD__)
 CHECK CheckUnderflow(SIZE_T value1, SIZE_T value2);
 #endif
 CHECK CheckUnderflow(const void *address, UINT offset);
 #if defined(_MSC_VER)
 CHECK CheckUnderflow(const void *address, ULONG offset);
 #endif
 CHECK CheckUnderflow(const void *address, UINT64 offset);
-#ifdef __APPLE__
+#if defined(__APPLE__) || defined(__OpenBSD__)
 CHECK CheckUnderflow(const void *address, SIZE_T offset);
 #endif
 CHECK CheckUnderflow(const void *address, void *address2);

src/coreclr/inc/check.inl

@@ -156,7 +156,7 @@ inline CHECK CheckAligned(UINT64 value, UINT alignment)
     CHECK_OK;
 }
 
-#if defined(__APPLE__) || defined(__wasm__)
+#if defined(__APPLE__) || defined(__wasm__) || defined(__OpenBSD__)
 inline CHECK CheckAligned(SIZE_T value, UINT alignment)
 {
     STATIC_CONTRACT_WRAPPER;
@@ -192,7 +192,7 @@ inline CHECK CheckOverflow(UINT64 value1, UINT64 value2)
     CHECK_OK;
 }
 
-#ifdef __APPLE__
+#if defined(__APPLE__) || defined(__OpenBSD__)
 inline CHECK CheckOverflow(SIZE_T value1, SIZE_T value2)
 {
     CHECK(value1 + value2 >= value1);
@@ -237,7 +237,7 @@ inline CHECK CheckOverflow(const void *address, UINT64 offset)
     CHECK_OK;
 }
 
-#if defined(__APPLE__) || defined(__wasm__)
+#if defined(__APPLE__) || defined(__wasm__) || defined(__OpenBSD__)
 inline CHECK CheckOverflow(const void *address, SIZE_T offset)
 {
     CHECK((UINT64) address + offset >= (UINT64) address);
@@ -271,7 +271,7 @@ inline CHECK CheckUnderflow(UINT64 value1, UINT64 value2)
     CHECK_OK;
 }
 
-#ifdef __APPLE__
+#if defined(__APPLE__) || defined(__OpenBSD__)
 inline CHECK CheckUnderflow(SIZE_T value1, SIZE_T value2)
 {
     CHECK(value1 - value2 <= value1);
@@ -316,7 +316,7 @@ inline CHECK CheckUnderflow(const void *address, UINT64 offset)
     CHECK_OK;
 }
 
-#if defined(__APPLE__) || defined(__wasm__)
+#if defined(__APPLE__) || defined(__wasm__) || defined(__OpenBSD__)
 inline CHECK CheckUnderflow(const void *address, SIZE_T offset)
 {
     // SIZE_T is 32bit on wasm32
@@ -371,4 +371,3 @@ inline CHECK CheckBounds(const void *rangeBase, UINT32 rangeSize, UINT32 offset,
 }
 
 #endif  // CHECK_INL_
-

src/coreclr/inc/clrtypes.h

@@ -1,5 +1,6 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
+
 // ================================================================================
 // Standard primitive types for CLR code
 //
@@ -275,7 +276,7 @@ inline UINT64 AlignUp(UINT64 value, UINT alignment)
     return (value+alignment-1)&~(UINT64)(alignment-1);
 }
 
-#if defined(__APPLE__) || defined(__wasm__)
+#if defined(__APPLE__) || defined(__wasm__) || defined(__OpenBSD__)
 inline SIZE_T AlignUp(SIZE_T value, UINT alignment)
 {
     STATIC_CONTRACT_LEAF;
@@ -316,7 +317,7 @@ inline uintptr_t AlignDown(uintptr_t value, UINT alignment)
 }
 #endif
 
-#ifdef __APPLE__
+#if defined(__APPLE__) || defined(__OpenBSD__)
 inline SIZE_T AlignDown(SIZE_T value, UINT alignment)
 {
     STATIC_CONTRACT_LEAF;
@@ -345,7 +346,7 @@ inline UINT AlignmentPad(UINT64 value, UINT alignment)
     return (UINT) (AlignUp(value, alignment) - value);
 }
 
-#if defined(__APPLE__) || defined(__wasm__)
+#if defined(__APPLE__) || defined(__wasm__) || defined(__OpenBSD__)
 inline UINT AlignmentPad(SIZE_T value, UINT alignment)
 {
     STATIC_CONTRACT_WRAPPER;
@@ -378,7 +379,7 @@ inline UINT AlignmentTrim(UINT64 value, UINT alignment)
     return ((UINT)value)&(alignment-1);
 }
 
-#if defined(__APPLE__) || defined(__wasm__)
+#if defined(__APPLE__) || defined(__wasm__) || defined(__OpenBSD__)
 inline UINT AlignmentTrim(SIZE_T value, UINT alignment)
 {
     STATIC_CONTRACT_LEAF;

src/coreclr/inc/pedecoder.h

@@ -102,6 +102,8 @@ inline CHECK CheckOverflow(RVA value1, COUNT_T value2)
 #define IMAGE_FILE_MACHINE_NATIVE_OS_OVERRIDE 0x4644
 #elif defined(__FreeBSD__)
 #define IMAGE_FILE_MACHINE_NATIVE_OS_OVERRIDE 0xADC4
+#elif defined(__OpenBSD__)
+#define IMAGE_FILE_MACHINE_NATIVE_OS_OVERRIDE 0xADC5
 #elif defined(__linux__)
 #define IMAGE_FILE_MACHINE_NATIVE_OS_OVERRIDE 0x7B79
 #elif defined(__NetBSD__)

src/coreclr/jit/compiler.hpp

@@ -141,12 +141,12 @@ inline unsigned genLog2(uint64_t value)
     return BitOperations::BitScanForward(value);
 }
 
-#ifdef __APPLE__
+#if defined(__APPLE__) || defined(__OpenBSD__)
 inline unsigned genLog2(size_t value)
 {
     return genLog2((uint64_t)value);
 }
-#endif // __APPLE__
+#endif // __APPLE__ || __OpenBSD__
 
 // Given an unsigned 64-bit value, returns the lower 32-bits in unsigned format
 //

src/coreclr/jit/jit.h

@@ -731,12 +731,12 @@ inline size_t unsigned_abs(ssize_t x)
     return ((size_t)std::abs((int64_t)x));
 }
 
-#ifdef __APPLE__
+#if defined(__APPLE__) || defined(__OpenBSD__)
 inline size_t unsigned_abs(int64_t x)
 {
     return ((size_t)std::abs(x));
 }
-#endif // __APPLE__
+#endif // __APPLE__ || __OpenBSD__
 #endif // TARGET_64BIT
 
 /*****************************************************************************/

src/coreclr/minipal/Unix/doublemapping.cpp

@@ -1,6 +1,5 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
-//
 
 #include <stddef.h>
 #include <sys/mman.h>
@@ -102,6 +101,8 @@ bool VMToOSInterface::CreateDoubleMemoryMapper(void** pHandle, size_t *pMaxExecu
     // Clip the maximum double mapped memory size to 1/4 of the virtual address space limit.
     // When such a limit is set, GC reserves 1/2 of it, so we need to leave something
     // for the rest of the process.
+#ifdef RLIMIT_AS
+    // OpenBSD has no address-space rlimit (RLIMIT_AS), so this clipping is skipped there.
     struct rlimit virtualAddressSpaceLimit;
     if ((getrlimit(RLIMIT_AS, &virtualAddressSpaceLimit) == 0) && (virtualAddressSpaceLimit.rlim_cur != RLIM_INFINITY))
     {
@@ -111,6 +112,7 @@ bool VMToOSInterface::CreateDoubleMemoryMapper(void** pHandle, size_t *pMaxExecu
             maxDoubleMappedMemorySize = virtualAddressSpaceLimit.rlim_cur;
         }
     }
+#endif // RLIMIT_AS
 
     // Clip the maximum double mapped memory size to the file size limit
     struct rlimit fileSizeLimit;

src/coreclr/nativeaot/BuildIntegration/Microsoft.NETCore.Native.Unix.targets

@@ -21,6 +21,7 @@ The .NET Foundation licenses this file to you under the MIT license.
     <CppLibCreator>ar</CppLibCreator>
     <_SymbolPrefix Condition="'$(_IsApplePlatform)' == 'true'">_</_SymbolPrefix>
     <LinkerFlavor Condition="'$(LinkerFlavor)' == '' and '$(_targetOS)' == 'freebsd'">lld</LinkerFlavor>
+    <LinkerFlavor Condition="'$(LinkerFlavor)' == '' and '$(_targetOS)' == 'openbsd'">lld</LinkerFlavor>
     <LinkerFlavor Condition="'$(LinkerFlavor)' == '' and '$(_linuxLibcFlavor)' == 'bionic'">lld</LinkerFlavor>
     <LinkerFlavor Condition="'$(LinkerFlavor)' == '' and '$(_targetOS)' == 'android'">lld</LinkerFlavor>
     <LinkerFlavor Condition="'$(LinkerFlavor)' == '' and '$(_targetOS)' == 'linux'">bfd</LinkerFlavor>
@@ -65,6 +66,7 @@ The .NET Foundation licenses this file to you under the MIT license.
       <TargetTriple Condition="'$(CrossCompileArch)' != '' and '$(_IsAlpineExitCode)' != '0'">$(CrossCompileArch)-linux-$(CrossCompileAbi)</TargetTriple>
       <TargetTriple Condition="'$(CrossCompileArch)' != '' and '$(_IsAlpineExitCode)' == '0'">$(CrossCompileArch)-alpine-linux-$(CrossCompileAbi)</TargetTriple>
       <TargetTriple Condition="'$(CrossCompileArch)' != '' and ($(CrossCompileRid.StartsWith('freebsd')))">$(CrossCompileArch)-unknown-freebsd12</TargetTriple>
+      <TargetTriple Condition="'$(CrossCompileArch)' != '' and ($(CrossCompileRid.StartsWith('openbsd')))">$(CrossCompileArch)-unknown-openbsd</TargetTriple>
 
       <SharedLibraryInstallName Condition="'$(SharedLibraryInstallName)' == '' and '$(_IsApplePlatform)' == 'true' and '$(NativeLib)' == 'Shared'">@rpath/$(NativeBinaryPrefix)$(TargetName)$(NativeBinaryExt)</SharedLibraryInstallName>
 
@@ -222,14 +224,14 @@ The .NET Foundation licenses this file to you under the MIT license.
 
     <ItemGroup>
       <NativeSystemLibrary Include="stdc++" Condition="'$(LinkStandardCPlusPlusLibrary)' == 'true'" />
-      <NativeSystemLibrary Include="dl" />
+      <NativeSystemLibrary Include="dl" Condition="'$(_targetOS)' != 'openbsd'" />
       <NativeSystemLibrary Include="objc" Condition="'$(_IsApplePlatform)' == 'true'" />
       <NativeSystemLibrary Include="swiftCore" Condition="'$(_IsApplePlatform)' == 'true'" />
       <NativeSystemLibrary Include="swiftFoundation" Condition="'$(_IsApplePlatform)' == 'true'" />
       <NativeSystemLibrary Include="z" Condition="'$(UseSystemZlib)' == 'true'" />
       <NativeSystemLibrary Include="brotlienc;brotlidec;brotlicommon" Condition="'$(UseSystemBrotli)' == 'true'" />
       <NativeSystemLibrary Include="zstd" Condition="'$(UseSystemZstd)' == 'true'" />
-      <NativeSystemLibrary Include="rt" Condition="'$(_IsApplePlatform)' != 'true' and '$(_linuxLibcFlavor)' != 'bionic'" />
+      <NativeSystemLibrary Include="rt" Condition="'$(_IsApplePlatform)' != 'true' and '$(_linuxLibcFlavor)' != 'bionic' and '$(_targetOS)' != 'openbsd'" />
       <NativeSystemLibrary Include="log" Condition="'$(_linuxLibcFlavor)' == 'bionic'" />
       <NativeSystemLibrary Include="icucore" Condition="'$(_IsApplePlatform)' == 'true'" />
       <NativeSystemLibrary Include="m" />

src/coreclr/nativeaot/CMakeLists.txt

@@ -28,6 +28,15 @@ if(CLR_CMAKE_TARGET_ANDROID)
     set(FEATURE_JAVAMARSHAL 1)
 endif()
 
+if(CLR_CMAKE_TARGET_OPENBSD)
+    # Use native (not emulated) TLS so C/C++ thread locals match the runtime's assembly.
+    add_compile_options(-fno-emulated-tls)
+
+    # OpenBSD has no __tls_get_addr (only static TLS). Use initial-exec so general-dynamic
+    # TLS (and its unresolvable __tls_get_addr reference in shared objects) is never emitted.
+    add_compile_options(-ftls-model=initial-exec)
+endif()
+
 if(NOT DEFINED FEATURE_JAVAMARSHAL)
   set(FEATURE_JAVAMARSHAL $<IF:$<CONFIG:Debug,Checked>,1,0>)
 endif()