From: Alexandre Oliva <oliva@adacore.com>
Date: Wed, 20 Dec 2023 00:06:22 +0000 (-0300)
Subject: strub: avoid lto inlining
X-Git-Tag: basepoints/gcc-15~3412
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=1b83fce7df32c72bf8e0c766e5ccb285801bce15;p=thirdparty%2Fgcc.git

strub: avoid lto inlining

The strub builtins are not suited for cross-unit inlining, they should
only be inlined by the builtin expanders, if at all.  While testing on
sparc64, it occurred to me that, if libgcc was built with LTO enabled,
lto1 might inline them, and that would likely break things.  So, make
sure they're clearly marked as not inlinable.


for  libgcc/ChangeLog

	* strub.c (ATTRIBUTE_NOINLINE): New.
	(ATTRIBUTE_STRUB_CALLABLE): Add it.
	(__strub_dummy_force_no_leaf): Drop it.
---

diff --git a/libgcc/strub.c b/libgcc/strub.c
index b0f990d9deeb..3b7cc26b3d8f 100644
--- a/libgcc/strub.c
+++ b/libgcc/strub.c
@@ -36,7 +36,12 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 # define TOPS <
 #endif
 
-#define ATTRIBUTE_STRUB_CALLABLE __attribute__ ((__strub__ ("callable")))
+/* Make sure these builtins won't be inlined, even with LTO.  */
+#define ATTRIBUTE_NOINLINE \
+  __attribute__ ((__noinline__, __noclone__, __noipa__))
+
+#define ATTRIBUTE_STRUB_CALLABLE \
+  __attribute__ ((__strub__ ("callable"))) ATTRIBUTE_NOINLINE
 
 /* Enter a stack scrubbing context, initializing the watermark to the caller's
    stack address.  */
@@ -72,7 +77,6 @@ __strub_update (void **watermark)
 /* Dummy function, called to force the caller to not be a leaf function, so
    that it can't use the red zone.  */
 static void ATTRIBUTE_STRUB_CALLABLE
-__attribute__ ((__noinline__, __noipa__))
 __strub_dummy_force_no_leaf (void)
 {
 }