diff --git a/Makefile b/Makefile
index 1a44c811aa5633..08d9961425dbb8 100644
--- a/Makefile
+++ b/Makefile
@@ -427,6 +427,8 @@ all::
 #
 # Define HAVE_GETDELIM if your system has the getdelim() function.
 #
+# Define FILENO_IS_A_MACRO if fileno() is a macro, not a real function.
+#
 # Define PAGER_ENV to a SP separated VAR=VAL pairs to define
 # default environment variables to be passed when a pager is spawned, e.g.
 #
@@ -1773,6 +1775,11 @@ ifdef HAVE_WPGMPTR
 	BASIC_CFLAGS += -DHAVE_WPGMPTR
 endif
 
+ifdef FILENO_IS_A_MACRO
+	COMPAT_CFLAGS += -DFILENO_IS_A_MACRO
+	COMPAT_OBJS += compat/fileno.o
+endif
+
 ifeq ($(TCLTK_PATH),)
 NO_TCLTK = NoThanks
 endif
diff --git a/compat/fileno.c b/compat/fileno.c
new file mode 100644
index 00000000000000..7b105f4cd71a4e
--- /dev/null
+++ b/compat/fileno.c
@@ -0,0 +1,7 @@
+#define COMPAT_CODE
+#include "../git-compat-util.h"
+
+int git_fileno(FILE *stream)
+{
+	return fileno(stream);
+}
diff --git a/config.mak.uname b/config.mak.uname
index 3ee7da0e230c4c..23eac5ac9dca64 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -221,6 +221,7 @@ ifeq ($(uname_S),FreeBSD)
 	HAVE_BSD_KERN_PROC_SYSCTL = YesPlease
 	PAGER_ENV = LESS=FRX LV=-c MORE=FRX
 	FREAD_READS_DIRECTORIES = UnfortunatelyYes
+	FILENO_IS_A_MACRO = UnfortunatelyYes
 endif
 ifeq ($(uname_S),OpenBSD)
 	NO_STRCASESTR = YesPlease
@@ -233,6 +234,7 @@ ifeq ($(uname_S),OpenBSD)
 	HAVE_BSD_SYSCTL = YesPlease
 	HAVE_BSD_KERN_PROC_SYSCTL = YesPlease
 	PROCFS_EXECUTABLE_PATH = /proc/curproc/file
+	FILENO_IS_A_MACRO = UnfortunatelyYes
 endif
 ifeq ($(uname_S),MirBSD)
 	NO_STRCASESTR = YesPlease
diff --git a/git-compat-util.h b/git-compat-util.h
index 09b0102cae8c8c..7899f42f5ebbd7 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1220,6 +1220,14 @@ struct tm *git_gmtime_r(const time_t *, struct tm *);
 #define getc_unlocked(fh) getc(fh)
 #endif
 
+#ifdef FILENO_IS_A_MACRO
+int git_fileno(FILE *stream);
+# ifndef COMPAT_CODE
+#  undef fileno
+#  define fileno(p) git_fileno(p)
+# endif
+#endif
+
 /*
  * Our code often opens a path to an optional file, to work on its
  * contents when we can successfully open it.  We can ignore a failure