git: 30ed48b0a50a - main - clang: Skip attempts to access /proc/self/fd

The branch main has been updated by mjg:

URL: https://cgit.FreeBSD.org/src/commit/?id=30ed48b0a50a062415addcac216371a55e1f6a66

commit 30ed48b0a50a062415addcac216371a55e1f6a66
Author:     Mateusz Guzik <mjg@FreeBSD.org>
AuthorDate: 2022-03-27 18:01:38 +0000
Commit:     Mateusz Guzik <mjg@FreeBSD.org>
CommitDate: 2022-03-27 18:01:38 +0000

    clang: Skip attempts to access /proc/self/fd
    
    In contrast to Linux it does not provide entries which can be readlinked
    -- these are just regular files, not giving the expected outcome. That's
    on top of procfs not being mounted by default to begin with.
    
    Reviewed by:    dim
    Differential Revision:          https://reviews.freebsd.org/D34684
---
 contrib/llvm-project/llvm/lib/Support/Unix/Path.inc | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/contrib/llvm-project/llvm/lib/Support/Unix/Path.inc b/contrib/llvm-project/llvm/lib/Support/Unix/Path.inc
index c37b3a54644a..8c2af5ee0f8d 100644
--- a/contrib/llvm-project/llvm/lib/Support/Unix/Path.inc
+++ b/contrib/llvm-project/llvm/lib/Support/Unix/Path.inc
@@ -930,7 +930,15 @@ ErrorOr<basic_file_status> directory_entry::status() const {
   return s;
 }
 
-#if !defined(F_GETPATH)
+//
+// FreeBSD optionally provides /proc/self/fd, but it is incompatible with
+// Linux. The thing to use is realpath.
+//
+#if !defined(__FreeBSD__)
+#define TRY_PROC_SELF_FD
+#endif
+
+#if !defined(F_GETPATH) && defined(TRY_PROC_SELF_FD)
 static bool hasProcSelfFD() {
   // If we have a /proc filesystem mounted, we can quickly establish the
   // real name of the file with readlink
@@ -1117,6 +1125,7 @@ std::error_code openFileForRead(const Twine &Name, int &ResultFD,
     RealPath->append(Buffer, Buffer + strlen(Buffer));
 #else
   char Buffer[PATH_MAX];
+#if defined(TRY_PROC_SELF_FD)
   if (hasProcSelfFD()) {
     char ProcPath[64];
     snprintf(ProcPath, sizeof(ProcPath), "/proc/self/fd/%d", ResultFD);
@@ -1124,13 +1133,16 @@ std::error_code openFileForRead(const Twine &Name, int &ResultFD,
     if (CharCount > 0)
       RealPath->append(Buffer, Buffer + CharCount);
   } else {
+#endif
     SmallString<128> Storage;
     StringRef P = Name.toNullTerminatedStringRef(Storage);
 
     // Use ::realpath to get the real path name
     if (::realpath(P.begin(), Buffer) != nullptr)
       RealPath->append(Buffer, Buffer + strlen(Buffer));
+#if defined(TRY_PROC_SELF_FD)
   }
+#endif
 #endif
   return std::error_code();
 }