1From ebbc5e14cdbfcc24bf3c9bb7b41ee10cd979c535 Mon Sep 17 00:00:00 2001
2From: serge-sans-paille <serge.guelton@telecom-bretagne.eu>
3Date: Thu, 2 Feb 2023 11:40:17 +0000
4Subject: [PATCH] Fix signed vs unsigned comparison (#765)
5
6As reported by -Wsign-compare. In the case of getting the result of
7comparing the result of sysconf (_SC_PAGESIZE) to other value, this also
8correctly handles edge cases where the above fails and returns -1.
9
10Co-authored-by: serge-sans-paille <sguelton@mozilla.com>
11---
12 src/closures.c | 2 +-
13 src/prep_cif.c | 2 +-
14 src/tramp.c    | 7 +++++--
15 3 files changed, 7 insertions(+), 4 deletions(-)
16
17diff --git a/src/closures.c b/src/closures.c
18index 9aafbec4b..c42527795 100644
19--- a/src/closures.c
20+++ b/src/closures.c
21@@ -795,7 +795,7 @@ open_temp_exec_file (void)
22 static int
23 allocate_space (int fd, off_t offset, off_t len)
24 {
25-  static size_t page_size;
26+  static long page_size;
27 
28   /* Obtain system page size. */
29   if (!page_size)
30diff --git a/src/prep_cif.c b/src/prep_cif.c
31index 2d0f2521f..0e2d58e5e 100644
32--- a/src/prep_cif.c
33+++ b/src/prep_cif.c
34@@ -234,7 +234,7 @@ ffi_status ffi_prep_cif_var(ffi_cif *cif,
35 {
36   ffi_status rc;
37   size_t int_size = ffi_type_sint.size;
38-  int i;
39+  unsigned int i;
40 
41   rc = ffi_prep_cif_core(cif, abi, 1, nfixedargs, ntotalargs, rtype, atypes);
42 
43diff --git a/src/tramp.c b/src/tramp.c
44index b9d273a1a..7e005b054 100644
45--- a/src/tramp.c
46+++ b/src/tramp.c
47@@ -266,7 +266,7 @@ ffi_tramp_get_temp_file (void)
48    * trampoline table to make sure that the temporary file can be mapped.
49    */
50   count = write(tramp_globals.fd, tramp_globals.text, tramp_globals.map_size);
51-  if (count == tramp_globals.map_size && tramp_table_alloc ())
52+  if (count >=0 && (size_t)count == tramp_globals.map_size && tramp_table_alloc ())
53     return 1;
54 
55   close (tramp_globals.fd);
56@@ -374,6 +374,8 @@ tramp_table_unmap (struct tramp_table *table)
57 static int
58 ffi_tramp_init (void)
59 {
60+  long page_size;
61+
62   if (tramp_globals.status == TRAMP_GLOBALS_PASSED)
63     return 1;
64 
65@@ -396,7 +398,8 @@ ffi_tramp_init (void)
66     &tramp_globals.map_size);
67   tramp_globals.ntramp = tramp_globals.map_size / tramp_globals.size;
68 
69-  if (sysconf (_SC_PAGESIZE) > tramp_globals.map_size)
70+  page_size = sysconf (_SC_PAGESIZE);
71+  if (page_size >= 0 && (size_t)page_size > tramp_globals.map_size)
72     return 0;
73 
74   if (ffi_tramp_init_os ())
75