From: Lasse Collin <lasse.collin@tukaani.org>
Date: Sun, 2 Nov 2025 15:45:20 +0000 (+0200)
Subject: xz: Silence a warning from Clang on glibc systems
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=beca015891fbd22657663ec23809184dda0677cd;p=thirdparty%2Fxz.git

xz: Silence a warning from Clang on glibc systems

Fixes: e8838b2f5922 ("xz: Look at resource limits when determining the default memlimit")
---

diff --git a/src/xz/hardware.c b/src/xz/hardware.c
index 2e921474..3a1a709f 100644
--- a/src/xz/hardware.c
+++ b/src/xz/hardware.c
@@ -351,6 +351,16 @@ hardware_init(void)
 	const rlim_t margin = 64 << 20;
 
 	for (size_t i = 0; i < ARRAY_SIZE(resources); ++i) {
+		// glibc: When GNU extensions are enabled, <sys/resource.h>
+		// declares getrlimit() so that the first argument is an enum
+		// instead of int as in POSIX. GCC and Clang use unsigned int
+		// for enums when possible, so a sign conversion occurs when
+		// resources[i] is convert to the enum type. Clang warns about
+		// this with -Wsign-conversion but GCC doesn't.
+#ifdef __clang__
+#	pragma GCC diagnostic push
+#	pragma GCC diagnostic ignored "-Wsign-conversion"
+#endif
 		// RLIM_SAVED_* might be used on some 32-bit OSes
 		// (AIX at least) when the limit doesn't fit in a 32-bit
 		// unsigned integer. Thus, for us these are the same thing
@@ -360,6 +370,9 @@ hardware_init(void)
 				&& rl.rlim_cur != RLIM_INFINITY
 				&& rl.rlim_cur != RLIM_SAVED_CUR
 				&& rl.rlim_cur != RLIM_SAVED_MAX) {
+#ifdef __clang__
+#	pragma GCC diagnostic pop
+#endif
 			// Subtract the margin from the current resource
 			// limit, but avoid negative results. Avoid also 0
 			// because hardware_memlimit_show() (--info-memory)