[libc] Fix allocator inclusion

[michaelrj]

Summary

Previously, allocator functions were only available if they were included
from scudo or by using the system libc headers (i.e. by turning off the
full build). This patch changes the logic to include the prototypes for
the allocator functitons in all cases, which allows the linker to link
in the system's allocator.

[abrachet]

Does something similar need to happen to the arm entrypoint file?

[sivachandra]

+1 @abrachet's suggestion about updating aarch64 list.

[michaelrj]

add allocator functions + strdup to aarch64 entrypoints list

libc/config/linux/aarch64/entrypoints.txt

set(TARGET_LIBC_ENTRYPOINTS
     libc.src.string.strnlen
     libc.src.string.strpbrk
     libc.src.string.strrchr
     libc.src.string.strspn
     libc.src.string.strstr
     libc.src.string.strtok
     libc.src.string.strtok_r
 
+    # string.h entrypoints that depend on malloc
+    libc.src.string.strdup
+    libc.src.string.strndup
+
     # inttypes.h entrypoints
     libc.src.inttypes.imaxdiv
     libc.src.inttypes.strtoimax
     libc.src.inttypes.strtoumax
 
     # stdlib.h entrypoints
     libc.src.stdlib.abs
     libc.src.stdlib.atoi
set(TARGET_LIBC_ENTRYPOINTS
     libc.src.stdlib.strtod
     libc.src.stdlib.strtof
     libc.src.stdlib.strtol
     libc.src.stdlib.strtold
     libc.src.stdlib.strtoll
     libc.src.stdlib.strtoul
     libc.src.stdlib.strtoull
 
+    # stdlib.h external entrypoints
+    libc.src.stdlib.malloc
+    libc.src.stdlib.calloc
+    libc.src.stdlib.realloc
+    libc.src.stdlib.free
+
     # sys/stat.h entrypoints
     libc.src.sys.stat.mkdir
     libc.src.sys.stat.mkdirat
 
     # unistd.h entrypoints
     libc.src.unistd.close
     libc.src.unistd.fsync
     libc.src.unistd.read

libc/config/linux/x86_64/entrypoints.txt

set(TARGET_LIBC_ENTRYPOINTS
     libc.src.string.strnlen
     libc.src.string.strpbrk
     libc.src.string.strrchr
     libc.src.string.strspn
     libc.src.string.strstr
     libc.src.string.strtok
     libc.src.string.strtok_r
 
+    # string.h entrypoints that depend on malloc
+    libc.src.string.strdup
+    libc.src.string.strndup
+
     # inttypes.h entrypoints
     libc.src.inttypes.imaxdiv
     libc.src.inttypes.strtoimax
     libc.src.inttypes.strtoumax
 
     # stdlib.h entrypoints
     libc.src.stdlib.abs
     libc.src.stdlib.atoi
set(TARGET_LIBC_ENTRYPOINTS
     libc.src.stdlib.strtod
     libc.src.stdlib.strtof
     libc.src.stdlib.strtol
     libc.src.stdlib.strtold
     libc.src.stdlib.strtoll
     libc.src.stdlib.strtoul
     libc.src.stdlib.strtoull
 
+    # stdlib.h external entrypoints
+    libc.src.stdlib.malloc
+    libc.src.stdlib.calloc
+    libc.src.stdlib.realloc
+    libc.src.stdlib.free
+
     # sys/mman.h entrypoints
     libc.src.sys.mman.mmap
     libc.src.sys.mman.munmap
 
     # sys/stat.h entrypoints
     libc.src.sys.stat.mkdir
     libc.src.sys.stat.mkdirat
 
list(APPEND TARGET_LIBC_ENTRYPOINTS
     libc.src.time.asctime
     libc.src.time.asctime_r
     libc.src.time.gmtime
     libc.src.time.gmtime_r
     libc.src.time.mktime
   )
 endif()
 
-if(LLVM_LIBC_INCLUDE_SCUDO)
-  list(APPEND TARGET_LIBC_ENTRYPOINTS
-
-    # stdlib.h external entrypoints
-    libc.src.stdlib.malloc
-    libc.src.stdlib.calloc
-    libc.src.stdlib.realloc
-    libc.src.stdlib.free
-  )
-endif()
-
-if(LLVM_LIBC_INCLUDE_SCUDO OR NOT LLVM_LIBC_FULL_BUILD)
-  list(APPEND TARGET_LIBC_ENTRYPOINTS
-    # string.h entrypoints that depend on malloc
-    libc.src.string.strdup
-    libc.src.string.strndup
-  )
-endif()
-
 set(TARGET_LLVMLIBC_ENTRYPOINTS
   ${TARGET_LIBC_ENTRYPOINTS}
   ${TARGET_LIBM_ENTRYPOINTS}
 )

libc/src/__support/CPP/CMakeLists.txt

 # TODO(michaelrj): separate the standalone_cpp library into individual targets.
 add_header_library(
   standalone_cpp
   HDRS
     Array.h
     ArrayRef.h
     Bit.h
     Bitset.h
     Functional.h
     Limits.h
     StringView.h
     TypeTraits.h
 )
 
-if(LLVM_LIBC_INCLUDE_SCUDO OR NOT LLVM_LIBC_FULL_BUILD)
-  add_header_library(
-    vector
-    HDRS
-      vector.h
-    DEPENDS
-      libc.include.stdlib
-  )
-endif()

libc/src/stdlib/CMakeLists.txt

add_entrypoint_external(
     DEPENDS
       ${SCUDO_DEPS}
   )
   add_entrypoint_external(
     free
     DEPENDS
       ${SCUDO_DEPS}
   )
-
+else()
+  add_entrypoint_external(
+    malloc
+  )
+  add_entrypoint_external(
+    calloc
+  )
+  add_entrypoint_external(
+    realloc
+  )
+  add_entrypoint_external(
+    free
+  )
 endif()
 
 if(NOT LLVM_LIBC_FULL_BUILD)
   return()
 endif()
 
 if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_OS})
   add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_OS})

libc/test/utils/CPP/CMakeLists.txt

add_libc_unittest(
   SUITE
     libc_cpp_utils_unittests
   SRCS
     arrayref_test.cpp
   DEPENDS
     libc.src.__support.CPP.standalone_cpp
 )
 
-if(LLVM_LIBC_INCLUDE_SCUDO OR NOT LLVM_LIBC_FULL_BUILD)
-  add_libc_unittest(
-    vector_test
-    SUITE
-      libc_cpp_utils_unittests
-    SRCS
-      vector_test.cpp
-    DEPENDS
-      libc.src.__support.CPP.vector
-  )
-endif()