[libc-commits] [libc] 5b2b3d1 - [libc][cmake] Introduce add_type_header for OS/arch-specific types. (#220750)

[via libc-commits]

Author: Alexey Samsonov
Date: 2026-09-02T21:00:57-07:00
New Revision: 5b2b3d1b319c2ca9745e4b6602fd2bc802679757

URL: https://github.com/llvm/llvm-project/commit/5b2b3d1b319c2ca9745e4b6602fd2bc802679757
DIFF: https://github.com/llvm/llvm-project/commit/5b2b3d1b319c2ca9745e4b6602fd2bc802679757.diff

LOG: [libc][cmake] Introduce add_type_header for OS/arch-specific types. (#220750)

* Follow the existing model of `add_macro_header` and introduce
  `add_type_header` which implicitly adds OS-specific and arch-specific
  dependencies for type definitions;
* Since arch-specific definitions may depend on other types (e.g.
`ucontext_t` depends on `sigset_t`),
move arch-specific folder inclusion and types to the bottom of the list;
* Use `add_type_header` for only four types (so far) that require it -
`mcontext_t`, `ucontext_t`,
`loff_t`, and `struct sysinfo`. We can bulk-update everyone else, but
that might be easier to do once
  we have CMake formatter in place.

Added: 
    libc/include/llvm-libc-types/x86_64/CMakeLists.txt

Modified: 
    libc/include/llvm-libc-types/CMakeLists.txt

Removed: 
    


################################################################################
diff  --git a/libc/include/llvm-libc-types/CMakeLists.txt b/libc/include/llvm-libc-types/CMakeLists.txt
index 02b9adf88bcac..9bf17a14cee69 100644
--- a/libc/include/llvm-libc-types/CMakeLists.txt
+++ b/libc/include/llvm-libc-types/CMakeLists.txt
@@ -1,6 +1,39 @@
+# Helper function to set up dependencies if they exist.
+function(add_type_header name)
+  cmake_parse_arguments(
+    "TYPE_HEADER"
+    "" # Optional arguments
+    "HDR;DEST_HDR" # Single value arguments
+    "DEPENDS" # Multi-value arguments
+    ${ARGN}
+  )
+  if(TYPE_HEADER_DEST_HDR)
+    set(dest_header_arg DEST_HDR ${TYPE_HEADER_DEST_HDR})
+  endif()
+  set(deps)
+  if(TARGET libc.include.llvm-libc-types.${LIBC_TARGET_OS}.${name})
+    list(APPEND deps .${LIBC_TARGET_OS}.${name})
+  endif()
+  if(TARGET libc.include.llvm-libc-types.${LIBC_TARGET_ARCHITECTURE}.${name})
+    list(APPEND deps .${LIBC_TARGET_ARCHITECTURE}.${name})
+  endif()
+  if(TYPE_HEADER_DEPENDS)
+    list(APPEND deps ${TYPE_HEADER_DEPENDS})
+  endif()
+  add_header(
+    ${name}
+    HDR
+      ${TYPE_HEADER_HDR}
+    ${dest_header_arg}
+    DEPENDS
+      ${deps}
+  )
+endfunction()
+
 if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_OS})
   add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_OS})
 endif()
+
 add_header(off64_t HDR off64_t.h)
 add_header(size_t HDR size_t.h)
 add_header(
@@ -67,11 +100,11 @@ add_header(
 )
 add_header(ldiv_t HDR ldiv_t.h)
 add_header(lldiv_t HDR lldiv_t.h)
-if(TARGET libc.include.llvm-libc-types.${LIBC_TARGET_OS}.loff_t)
-  add_header(loff_t HDR loff_t.h DEPENDS .${LIBC_TARGET_OS}.loff_t)
-else()
-  add_header(loff_t HDR loff_t.h)
-endif()
+add_type_header(
+  loff_t
+  HDR
+    loff_t.h
+)
 add_header(FILE HDR FILE.h)
 add_header(fd_set HDR fd_set.h DEPENDS libc.include.llvm-libc-macros.sys_select_macros)
 add_header(fenv_t HDR fenv_t.h)
@@ -174,30 +207,6 @@ add_header(union_sigval HDR union_sigval.h)
 add_header(siginfo_t HDR siginfo_t.h DEPENDS .union_sigval .pid_t .uid_t .clock_t)
 add_header(sig_atomic_t HDR sig_atomic_t.h)
 add_header(sigset_t HDR sigset_t.h DEPENDS libc.include.llvm-libc-macros.signal_macros)
-set(mcontext_deps)
-set(ucontext_deps .sigset_t .stack_t)
-
-if(LIBC_TARGET_ARCHITECTURE STREQUAL "x86_64")
-  add_header(
-    mcontext_t_arch
-    HDR
-      x86_64/mcontext_t.h
-  )
-  add_header(
-    ucontext_t_arch
-    HDR
-      x86_64/ucontext_t.h
-    DEPENDS
-      .mcontext_t_arch
-      .sigset_t
-      .stack_t
-  )
-  list(APPEND mcontext_deps .mcontext_t_arch)
-  list(APPEND ucontext_deps .ucontext_t_arch)
-endif()
-
-add_header(mcontext_t HDR mcontext_t.h DEPENDS ${mcontext_deps})
-add_header(ucontext_t HDR ucontext_t.h DEPENDS .mcontext_t ${ucontext_deps})
 add_header(u_char HDR u_char.h)
 add_header(u_int32_t HDR u_int32_t.h)
 add_header(uint HDR uint.h)
@@ -218,11 +227,11 @@ add_header(
 add_header(struct_tm HDR struct_tm.h)
 add_header(struct_passwd HDR struct_passwd.h DEPENDS .uid_t .gid_t)
 add_header(struct_group HDR struct_group.h DEPENDS .gid_t)
-if(TARGET libc.include.llvm-libc-types.${LIBC_TARGET_OS}.struct_sysinfo)
-  add_header(struct_sysinfo HDR struct_sysinfo.h DEPENDS .${LIBC_TARGET_OS}.struct_sysinfo)
-else()
-  add_header(struct_sysinfo HDR struct_sysinfo.h)
-endif()
+add_type_header(
+  struct_sysinfo
+  HDR
+    struct_sysinfo.h
+)
 add_header(struct_utsname HDR struct_utsname.h)
 add_header(thrd_start_t HDR thrd_start_t.h)
 add_header(thrd_t HDR thrd_t.h DEPENDS .__thread_type)
@@ -603,6 +612,14 @@ add_header(
     .Elf64_Half
 )
 
+# Arch-specific types
+if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_ARCHITECTURE})
+  add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_ARCHITECTURE})
+endif()
+
+add_type_header(mcontext_t HDR mcontext_t.h)
+add_type_header(ucontext_t HDR ucontext_t.h)
+
 # UEFI
 add_header(EFI_GUID HDR EFI_GUID.h DEPENDS libc.include.llvm-libc-macros.stdint_macros)
 add_header(EFI_CONFIGURATION_TABLE HDR EFI_CONFIGURATION_TABLE.h DEPENDS .EFI_GUID)

diff  --git a/libc/include/llvm-libc-types/x86_64/CMakeLists.txt b/libc/include/llvm-libc-types/x86_64/CMakeLists.txt
new file mode 100644
index 0000000000000..a0b329365b1f1
--- /dev/null
+++ b/libc/include/llvm-libc-types/x86_64/CMakeLists.txt
@@ -0,0 +1,15 @@
+add_header(
+  mcontext_t
+  HDR
+    mcontext_t.h
+)
+
+add_header(
+  ucontext_t
+  HDR
+    ucontext_t.h
+  DEPENDS
+    .mcontext_t
+    libc.include.llvm-libc-types.sigset_t
+    libc.include.llvm-libc-types.stack_t
+)