[libc-commits] [libc] 6c2b155 - [libc] Fix build failures in fuzzing tests (#185017)

[via libc-commits]

Author: Victor Campos
Date: 2026-03-16T11:14:57Z
New Revision: 6c2b155f4f36d03a9ac5cef61f6e2082b985d61a

URL: https://github.com/llvm/llvm-project/commit/6c2b155f4f36d03a9ac5cef61f6e2082b985d61a
DIFF: https://github.com/llvm/llvm-project/commit/6c2b155f4f36d03a9ac5cef61f6e2082b985d61a.diff

LOG: [libc] Fix build failures in fuzzing tests (#185017)

The tests:
 - __support/freelist_heap_fuzz.cpp
 - fuzzing/string/strlen_fuzz.cpp

had build failures for different reasons. This patch fixes these
failures.

freelist_heap_fuzz.cpp had this error:

```
llvm-project/libc/fuzzing/__support/freelist_heap_fuzz.cpp:150:26: error: use of undeclared identifier 'Block'; did you mean '__llvm_libc_23_0_0_git::Block'?
  150 |       size_t alignment = Block::MIN_ALIGN;
      |                          ^~~~~
      |                          __llvm_libc_23_0_0_git::Block
```

The issue stems from the fact that Block was not available in scope. It
needs to be referenced via LIBC_NAMESPACE.

strlen_fuzz.cpp had this error:

```
In file included from Workspace/llvm-project/libc/fuzzing/string/strlen_fuzz.cpp:14:
In file included from /usr/lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/cstdint:38:
In file included from /usr/lib/gcc/x86_64-linux-gnu/13/../../../../include/x86_64-linux-gnu/c++/13/bits/c++config.h:679:
/usr/lib/gcc/x86_64-linux-gnu/13/../../../../include/x86_64-linux-gnu/c++/13/bits/os_defines.h:44:5: error: function-like macro '__GLIBC_PREREQ' is not defined
   44 | #if __GLIBC_PREREQ(2,15) && defined(_GNU_SOURCE)

```

This issue is more cryptic to me, but I managed to fix it by changing
the includes from cstdint and cstring to stdint.h and string.h.

Added: 
    

Modified: 
    libc/fuzzing/__support/freelist_heap_fuzz.cpp
    libc/fuzzing/string/strlen_fuzz.cpp

Removed: 
    


################################################################################
diff  --git a/libc/fuzzing/__support/freelist_heap_fuzz.cpp b/libc/fuzzing/__support/freelist_heap_fuzz.cpp
index b342b21895a08..3675e6c6b7adc 100644
--- a/libc/fuzzing/__support/freelist_heap_fuzz.cpp
+++ b/libc/fuzzing/__support/freelist_heap_fuzz.cpp
@@ -26,6 +26,7 @@ asm(R"(
 __llvm_libc_heap_limit:
 )");
 
+using LIBC_NAMESPACE::Block;
 using LIBC_NAMESPACE::FreeListHeap;
 using LIBC_NAMESPACE::inline_memset;
 using LIBC_NAMESPACE::cpp::nullopt;

diff  --git a/libc/fuzzing/string/strlen_fuzz.cpp b/libc/fuzzing/string/strlen_fuzz.cpp
index dd72c19b7fdc7..01b6bd14db230 100644
--- a/libc/fuzzing/string/strlen_fuzz.cpp
+++ b/libc/fuzzing/string/strlen_fuzz.cpp
@@ -11,8 +11,8 @@
 //===----------------------------------------------------------------------===//
 
 #include "src/string/strlen.h"
-#include <cstdint>
-#include <cstring>
+#include <stdint.h>
+#include <string.h>
 
 // always null terminate the data
 extern "C" size_t LLVMFuzzerMutate(uint8_t *data, size_t size, size_t max_size);