Without this patch, building coreutils with
--enable-gcc-checking=expensive would fail with a message like
“lib/exclude.c:682:6: error: leak of FILE 'in' [CWE-775]
[-Werror=analyzer-file-leak]”, because Gnulib replaced fclose but
not fopen, and GCC saw a call to fopen followed by a call to
rpl_fclose. The patch causes GCC to instead see a call to
rpl_fopen followed by rpl_fclose.
* m4/fclose.m4 (gl_FUNC_FCLOSE): Replace fopen when replacing
fclose.
* modules/fclose (Depends-on): Add fopen.
(configure.ac): Replace fopen when replacing fclose.
---
ChangeLog | 13 +++++++++++++
m4/fclose.m4 | 4 ++++
modules/fclose | 6 ++++++
3 files changed, 23 insertions(+)
diff --git a/ChangeLog b/ChangeLog
index 972aec03db..8d39a64023 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,18 @@
2023-04-24 Paul Eggert <egg...@cs.ucla.edu>
+ fclose: pacify gcc -Wanalyzer-file-leak
+ Without this patch, building coreutils with
+ --enable-gcc-checking=expensive would fail with a message like
+ “lib/exclude.c:682:6: error: leak of FILE 'in' [CWE-775]
+ [-Werror=analyzer-file-leak]”, because Gnulib replaced fclose but
+ not fopen, and GCC saw a call to fopen followed by a call to
+ rpl_fclose. The patch causes GCC to instead see a call to
+ rpl_fopen followed by rpl_fclose.
+ * m4/fclose.m4 (gl_FUNC_FCLOSE): Replace fopen when replacing
+ fclose.
+ * modules/fclose (Depends-on): Add fopen.
+ (configure.ac): Replace fopen when replacing fclose.
+
unsetenv-tests: pacify -Wanalyzer-putenv-of-auto-var
* tests/test-unsetenv.c (main): Make entry static. Even with this
change, it’s unclear whether this test is portable POSIX code, but
diff --git a/m4/fclose.m4 b/m4/fclose.m4
index dc021dd9f3..74b7df0a77 100644
--- a/m4/fclose.m4
+++ b/m4/fclose.m4
@@ -31,6 +31,10 @@ AC_DEFUN([gl_FUNC_FCLOSE],
*) REPLACE_FCLOSE=1 ;;
esac
fi
+
+ if test $REPLACE_FCLOSE = 1; then
+ REPLACE_FOPEN=1
+ fi
])
dnl Determine whether fclose works on input streams.
diff --git a/modules/fclose b/modules/fclose
index 703de9e686..9a949e48b8 100644
--- a/modules/fclose
+++ b/modules/fclose
@@ -9,12 +9,18 @@ Depends-on:
stdio
close [test $REPLACE_FCLOSE = 1]
fflush [test $REPLACE_FCLOSE = 1]
+fopen [test $REPLACE_FCLOSE = 1]
freading [test $REPLACE_FCLOSE = 1]
lseek [test $REPLACE_FCLOSE = 1]
msvc-inval [test $REPLACE_FCLOSE = 1]
configure.ac:
gl_FUNC_FCLOSE
+if test $REPLACE_FCLOSE = 1; then
+ REPLACE_FOPEN=1
+ AC_LIBOBJ([fopen])
+ gl_PREREQ_FOPEN
+fi
gl_CONDITIONAL([GL_COND_OBJ_FCLOSE], [test $REPLACE_FCLOSE = 1])
gl_STDIO_MODULE_INDICATOR([fclose])
--
2.40.0
