Commit 8c9c01ce authored by Madhavan Srinivasan's avatar Madhavan Srinivasan Committed by Michael Ellerman
Browse files

selftests/powerpc: Allow building without static libc 



Currently exec-target.c is linked statically with libc, which on Fedora
at least requires installing an additional package (glibc-static).

If that package is not installed the build fails with:

    CC       exec_target
  /usr/bin/ld: cannot find -lc: No such file or directory
  collect2: error: ld returned 1 exit status

All exec_target.c does is call sys_exit, which can be done easily enough
using inline assembly, and removes the requirement for a static libc to
be installed.

Suggested-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: default avatarMadhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240812094152.418586-1-maddy@linux.ibm.com
parent a5a670df

tools/testing/selftests/powerpc/benchmarks/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -18,4 +18,4 @@ $(OUTPUT)/context_switch: LDLIBS += -lpthread 


$(OUTPUT)/fork: LDLIBS += -lpthread



$(OUTPUT)/exec_target: CFLAGS += -static -nostartfiles
 
$(OUTPUT)/exec_target: CFLAGS += -nostartfiles

tools/testing/selftests/powerpc/benchmarks/exec_target.c

+14 −2
Original line number Diff line number Diff line
@@ -7,10 +7,22 @@ 
 */



#define _GNU_SOURCE

#include <unistd.h>

#include <sys/syscall.h>



void _start(void)

{

	syscall(SYS_exit, 0);

	asm volatile (

		"li %%r0, %[sys_exit];"

		"li %%r3, 0;"

		"sc;"

		:

		: [sys_exit] "i" (SYS_exit)

		/*

		 * "sc" will clobber r0, r3-r13, cr0, ctr, xer and memory.

		 * Even though sys_exit never returns, handle clobber

		 * registers.

		 */

		: "r0", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10",

		  "r11", "r12", "r13", "cr0", "ctr", "xer", "memory"

	);

}