x86emul/test: don't use *_len symbols

... as they don't work as intended with -fPIC.

I did prefer them over *_end ones at the time because older gcc would
cause .L* symbols to be public, due to issuing .globl for all
referenced externals. And labels at the end of instructions collide
with the ones at the start of the next instruction, making disassembly
harder to grok. Luckily recent gcc no longer issues those .globl
directives, and hence .L* labels, staying local by default, no longer
get in the way.

Reported-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Tested-by: Wei Liu <wei.liu2@citrix.com>

diff --git a/tools/tests/x86_emulator/test_x86_emulator.c b/tools/tests/x86_emulator/test_x86_emulator.c
index 245d1c69d666d60dbb7b5db7dd595630e0de2034..924fd36f18c21b7731abc5e1764f3fa52f53f93e 100644 (file)
--- a/tools/tests/x86_emulator/test_x86_emulator.c
+++ b/tools/tests/x86_emulator/test_x86_emulator.c
@@ -885,17 +885,16 @@ int main(int argc, char **argv)
     }
     printf("okay\n");
 
-#define decl_insn(which) extern const unsigned char which[], which##_len[]
+#define decl_insn(which) extern const unsigned char which[], \
+                         which##_end[] asm ( ".L" #which "_end" )
 #define put_insn(which, insn) ".pushsection .test, \"ax\", @progbits\n" \
                               #which ": " insn "\n"                     \
-                              ".equ " #which "_len, .-" #which "\n"     \
+                              ".L" #which "_end:\n"                     \
                               ".popsection"
 #define set_insn(which) (regs.eip = (unsigned long)(which))
 #define valid_eip(which) (regs.eip >= (unsigned long)(which) && \
-                          regs.eip < (unsigned long)(which) + \
-                                      (unsigned long)which##_len)
-#define check_eip(which) (regs.eip == (unsigned long)(which) + \
-                                      (unsigned long)which##_len)
+                          regs.eip < (unsigned long)which##_end)
+#define check_eip(which) (regs.eip == (unsigned long)which##_end)
 
     printf("%-40s", "Testing andn (%edx),%ecx,%ebx...");
     if ( stack_exec && cpu_has_bmi1 )