Re: [patchv2] Do not skip prologue for asm (.S) files

Re: [patchv2] Do not skip prologue for asm (.S) files

[Doug Evans]

Jan Kratochvil writes:
  > On Thu, 25 Jun 2015 22:42:48 +0200, Doug Evans wrote:
  > > Hmmm, so there's an undocumented requirement that minsym_found
  > > and find_function_start_sal work compatibly?
  > > [Which is actually not surprising if you know how linespecs and
  > > breakpoints: we find all the matching minsyms and fullsyms
  > > and then throw away the duplicates. But if these two functions
  > > behave differently then the search for duplicates fails. At least
  > > I'm guessing that's what happened here.]
  >
  > Yes:
  > # (gdb) file  
/root/jkratoch/redhat/gdb-clean/gdb/testsuite/gdb.base/breako2
  > # Reading symbols from  
/root/jkratoch/redhat/gdb-clean/gdb/testsuite/gdb.base/breako2...done.
  > # (gdb) break main
  > #-Breakpoint 1 at 0x10000644: file ./gdb.base/break.c, line 43.
  > #-(gdb) PASS: gdb.base/break.exp: breakpoint function, optimized file
  > #+Breakpoint 1 at 0x10000640: main. (2 locations)
  > #### Num     Type           Disp Enb Address            What
  > #### 1       breakpoint     keep y   <MULTIPLE>
  > #### 1.1                         y     0x0000000010000640 in main  
at ./gdb.base/break.c:42
  > #### 1.2                         y     0x0000000010000644 in main  
at ./gdb.base/break.c:43
  > #+(gdb) FAIL: gdb.base/break.exp: breakpoint function, optimized file
  > # break marker4
  > # Breakpoint 2 at 0x10000aa0: file ./gdb.base/break1.c, line 59.
  > # (gdb) PASS: gdb.base/break.exp: breakpoint small function, optimized  
file
  > #[...]
  > # Continuing.
  > #-720
  > #-Breakpoint 2, marker4 (d=177601976) at ./gdb.base/break1.c:59
  > #-59     void marker4 (long d) { values[0].a_field = d; }        /* set  
breakpoint 14 here */
  > #-(gdb) PASS: gdb.base/break.exp: run until breakpoint set at small  
function, optimized file (line bp_location14)
  > #+Breakpoint 1, main (argc=1, argv=0x3fffffffec48, envp=0x3fffffffec58)  
at ./gdb.base/break.c:43
  > #+43         if (argc == 12345) {  /* an unlikely value < 2^16, in case  
uninited */ /* set breakpoint 6 here */
  > #+(gdb) FAIL: gdb.base/break.exp: run until breakpoint set at small  
function, optimized file
  >
  >
  > > Can you do that, plus add a comment to both minsym_found
  > > and find_function_start_sal stating that we rely on them
  > > working compatibly.
  >
  > Done.  Providing for review the final patch given all the changes.
  >
  >
  > Thanks,
  > Jan
  > gdb/ChangeLog
  > 2015-06-26  Jan Kratochvil  <jan.kratochvil@redhat.com>
  >
  > 	* linespec.c (minsym_found): Reset sal.PC for COMPUNIT_LOCATIONS_VALID
  > 	and language_asm..
  > 	* symtab.c (find_function_start_sal): Likewise.
  >
  > gdb/testsuite/ChangeLog
  > 2015-06-20  Jan Kratochvil  <jan.kratochvil@redhat.com>
  >
  > 	* gdb.arch/amd64-prologue-skip.S: New file.
  > 	* gdb.arch/amd64-prologue-skip.exp: New file.

LGTM.

Thanks!

[commit] [patchv2] Do not skip prologue for asm (.S) files

[Jan Kratochvil]

On Fri, 26 Jun 2015 14:57:41 +0200, Doug Evans wrote:
> LGTM.

Checked in:
	6e22494e5076e4d3c0b2c2785883162f83db499e


Jan

Re: [patchv2] Do not skip prologue for asm (.S) files

[Jan Kratochvil]

[-- Attachment #1: Type: text/plain, Size: 2197 bytes --]

On Thu, 25 Jun 2015 22:42:48 +0200, Doug Evans wrote:
> Hmmm, so there's an undocumented requirement that minsym_found
> and find_function_start_sal work compatibly?
> [Which is actually not surprising if you know how linespecs and
> breakpoints: we find all the matching minsyms and fullsyms
> and then throw away the duplicates. But if these two functions
> behave differently then the search for duplicates fails. At least
> I'm guessing that's what happened here.]

Yes:
# (gdb) file /root/jkratoch/redhat/gdb-clean/gdb/testsuite/gdb.base/breako2
# Reading symbols from /root/jkratoch/redhat/gdb-clean/gdb/testsuite/gdb.base/breako2...done.
# (gdb) break main
#-Breakpoint 1 at 0x10000644: file ./gdb.base/break.c, line 43.
#-(gdb) PASS: gdb.base/break.exp: breakpoint function, optimized file
#+Breakpoint 1 at 0x10000640: main. (2 locations)
#### Num     Type           Disp Enb Address            What
#### 1       breakpoint     keep y   <MULTIPLE>      
#### 1.1                         y     0x0000000010000640 in main at ./gdb.base/break.c:42
#### 1.2                         y     0x0000000010000644 in main at ./gdb.base/break.c:43
#+(gdb) FAIL: gdb.base/break.exp: breakpoint function, optimized file
# break marker4
# Breakpoint 2 at 0x10000aa0: file ./gdb.base/break1.c, line 59.
# (gdb) PASS: gdb.base/break.exp: breakpoint small function, optimized file
#[...]
# Continuing.
#-720
#-Breakpoint 2, marker4 (d=177601976) at ./gdb.base/break1.c:59
#-59     void marker4 (long d) { values[0].a_field = d; }        /* set breakpoint 14 here */
#-(gdb) PASS: gdb.base/break.exp: run until breakpoint set at small function, optimized file (line bp_location14)
#+Breakpoint 1, main (argc=1, argv=0x3fffffffec48, envp=0x3fffffffec58) at ./gdb.base/break.c:43
#+43         if (argc == 12345) {  /* an unlikely value < 2^16, in case uninited */ /* set breakpoint 6 here */
#+(gdb) FAIL: gdb.base/break.exp: run until breakpoint set at small function, optimized file


> Can you do that, plus add a comment to both minsym_found
> and find_function_start_sal stating that we rely on them
> working compatibly.

Done.  Providing for review the final patch given all the changes.


Thanks,
Jan

[-- Attachment #2: 1 --]
[-- Type: text/plain, Size: 6008 bytes --]

gdb/ChangeLog
2015-06-26  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* linespec.c (minsym_found): Reset sal.PC for COMPUNIT_LOCATIONS_VALID
	and language_asm..
	* symtab.c (find_function_start_sal): Likewise.

gdb/testsuite/ChangeLog
2015-06-20  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* gdb.arch/amd64-prologue-skip.S: New file.
	* gdb.arch/amd64-prologue-skip.exp: New file.

diff --git a/gdb/linespec.c b/gdb/linespec.c
index d2089b5..65155d9 100644
--- a/gdb/linespec.c
+++ b/gdb/linespec.c
@@ -3432,7 +3432,9 @@ collect_symbols (struct symbol *sym, void *data)
 }
 
 /* We've found a minimal symbol MSYMBOL in OBJFILE to associate with our
-   linespec; return the SAL in RESULT.  */
+   linespec; return the SAL in RESULT.  This function should return SALs
+   matching those from find_function_start_sal, otherwise false
+   multiple-locations breakpoints could be placed.  */
 
 static void
 minsym_found (struct linespec_state *self, struct objfile *objfile,
@@ -3454,7 +3456,23 @@ minsym_found (struct linespec_state *self, struct objfile *objfile,
     sal = find_pc_sect_line (pc, NULL, 0);
 
   if (self->funfirstline)
-    skip_prologue_sal (&sal);
+    {
+      if (sal.symtab != NULL
+	  && (COMPUNIT_LOCATIONS_VALID (SYMTAB_COMPUNIT (sal.symtab))
+	      || SYMTAB_LANGUAGE (sal.symtab) == language_asm))
+	{
+	  /* If gdbarch_convert_from_func_ptr_addr does not apply then
+	     sal.SECTION, sal.LINE&co. will stay correct from above.
+	     If gdbarch_convert_from_func_ptr_addr applies then
+	     sal.SECTION is cleared from above and sal.LINE&co. will
+	     stay correct from the last find_pc_sect_line above.  */
+	  sal.pc = MSYMBOL_VALUE_ADDRESS (objfile, msymbol);
+	  sal.pc = gdbarch_convert_from_func_ptr_addr (gdbarch, sal.pc,
+						       &current_target);
+	}
+      else
+	skip_prologue_sal (&sal);
+    }
 
   if (maybe_add_address (self->addr_set, objfile->pspace, sal.pc))
     add_sal_to_sals (self, result, &sal, MSYMBOL_NATURAL_NAME (msymbol), 0);
diff --git a/gdb/symtab.c b/gdb/symtab.c
index 6693930..2b6af6c 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -3605,7 +3605,9 @@ find_pc_line_pc_range (CORE_ADDR pc, CORE_ADDR *startptr, CORE_ADDR *endptr)
 /* Given a function symbol SYM, find the symtab and line for the start
    of the function.
    If the argument FUNFIRSTLINE is nonzero, we want the first line
-   of real code inside the function.  */
+   of real code inside the function.
+   This function should return SALs matching those from minsym_found,
+   otherwise false multiple-locations breakpoints could be placed.  */
 
 struct symtab_and_line
 find_function_start_sal (struct symbol *sym, int funfirstline)
@@ -3617,6 +3619,14 @@ find_function_start_sal (struct symbol *sym, int funfirstline)
   section = SYMBOL_OBJ_SECTION (symbol_objfile (sym), sym);
   sal = find_pc_sect_line (BLOCK_START (SYMBOL_BLOCK_VALUE (sym)), section, 0);
 
+  if (funfirstline && sal.symtab != NULL
+      && (COMPUNIT_LOCATIONS_VALID (SYMTAB_COMPUNIT (sal.symtab))
+	  || SYMTAB_LANGUAGE (sal.symtab) == language_asm))
+    {
+      sal.pc = BLOCK_START (SYMBOL_BLOCK_VALUE (sym));
+      return sal;
+    }
+
   /* We always should have a line for the function start address.
      If we don't, something is odd.  Create a plain SAL refering
      just the PC and hope that skip_prologue_sal (if requested)
diff --git a/gdb/testsuite/gdb.arch/amd64-prologue-skip.S b/gdb/testsuite/gdb.arch/amd64-prologue-skip.S
new file mode 100644
index 0000000..66b806a
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/amd64-prologue-skip.S
@@ -0,0 +1,28 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2015 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+	.text
+/*0*/	hlt
+pushrbp: .globl pushrbp
+#define PUSHRBP push %rbp; mov %rsp, %rbp; nop
+/*1*/	PUSHRBP
+/*6*/	hlt
+
+/*7*/	hlt
+#define MINSYM nop; .globl minsym; minsym: nop
+/*8*/	MINSYM
+/*a*/	hlt
diff --git a/gdb/testsuite/gdb.arch/amd64-prologue-skip.exp b/gdb/testsuite/gdb.arch/amd64-prologue-skip.exp
new file mode 100644
index 0000000..015cd69
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/amd64-prologue-skip.exp
@@ -0,0 +1,35 @@
+# Copyright 2010-2015 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+standard_testfile .S
+set binfile ${binfile}.o
+
+if { ![istarget x86_64-*-* ] || ![is_lp64_target] } {
+    verbose "Skipping ${testfile}."
+    return
+}
+
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" object {debug}] != "" } {
+    untested ${testfile}
+    return
+}
+
+clean_restart ${binfile}
+
+gdb_test "break *pushrbp" " at 0x1: file .*"
+gdb_test "break pushrbp" " at 0x1: file .*"
+
+gdb_test "break *minsym" " at 0x9: file .*"
+gdb_test "break minsym" " at 0x9: file .*"

Re: [patchv2] Do not skip prologue for asm (.S) files

[Doug Evans]

Jan Kratochvil writes:
  > Hi Doug,
  >
  > Sergio has found a regression on ppc64 so I had to patch another  
function.
  > Now on ppc64:
  >
  > +Running  
/root/jkratoch/redhat/gdb-clean/gdb/testsuite/gdb.arch/amd64-prologue-skip.exp ...
  > -PASS: gdb.base/break.exp: run until function breakpoint, optimized file
  > +PASS: gdb.base/break.exp: run until function breakpoint, optimized file  
(code motion)
  > -PASS: gdb.threads/attach-many-short-lived-threads.exp: iter 3: attach
  > +XFAIL: gdb.threads/attach-many-short-lived-threads.exp: iter 3: attach  
(EPERM)
  >
  > Jan
  > gdb/ChangeLog
  > 2015-06-25  Jan Kratochvil  <jan.kratochvil@redhat.com>
  >
  > 	* dwarf2read.c (process_full_comp_unit): Set LOCATIONS_VALID also for
  > 	language_asm.
  > 	* linespec.c (minsym_found): Reset sal.PC for COMPUNIT_LOCATIONS_VALID.
  > 	* symtab.c (find_function_start_sal): Likewise.

Hmmm, so there's an undocumented requirement that minsym_found
and find_function_start_sal work compatibly?
[Which is actually not surprising if you know how linespecs and
breakpoints: we find all the matching minsyms and fullsyms
and then throw away the duplicates. But if these two functions
behave differently then the search for duplicates fails. At least
I'm guessing that's what happened here.]

Fortunately the check for SYMTAB_LANGUAGE should work here too.
Can you do that, plus add a comment to both minsym_found
and find_function_start_sal stating that we rely on them
working compatibly.

Thanks.

  > gdb/testsuite/ChangeLog
  > 2015-06-20  Jan Kratochvil  <jan.kratochvil@redhat.com>
  >
  > 	* gdb.arch/amd64-prologue-skip.S: New file.
  > 	* gdb.arch/amd64-prologue-skip.exp: New file.
  >
  > diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
  > index 496b74f..8bfd034 100644
  > --- a/gdb/dwarf2read.c
  > +++ b/gdb/dwarf2read.c
  > @@ -8094,7 +8094,7 @@ process_full_comp_unit (struct dwarf2_per_cu_data  
*per_cu,
  >  	 Still one can confuse GDB by using non-standard GCC compilation
  >  	 options - this waits on GCC PR other/32998 (-frecord-gcc-switches).
  >  	 */
  > -      if (cu->has_loclist && gcc_4_minor >= 5)
  > +      if ((cu->has_loclist && gcc_4_minor >= 5) || cu->language ==  
language_asm)
  >  	cust->locations_valid = 1;
  >
  >        if (gcc_4_minor >= 5)
  > diff --git a/gdb/linespec.c b/gdb/linespec.c
  > index d2089b5..e5b4c56 100644
  > --- a/gdb/linespec.c
  > +++ b/gdb/linespec.c
  > @@ -3454,7 +3454,22 @@ minsym_found (struct linespec_state *self, struct  
objfile *objfile,
  >      sal = find_pc_sect_line (pc, NULL, 0);
  >
  >    if (self->funfirstline)
  > -    skip_prologue_sal (&sal);
  > +    {
  > +      if (sal.symtab != NULL
  > +	  && COMPUNIT_LOCATIONS_VALID (SYMTAB_COMPUNIT (sal.symtab)))
  > +	{
  > +	  /* If gdbarch_convert_from_func_ptr_addr does not apply then
  > +	     sal.SECTION, sal.LINE&co. will stay correct from above.
  > +	     If gdbarch_convert_from_func_ptr_addr applies then
  > +	     sal.SECTION is cleared from above and sal.LINE&co. will
  > +	     stay correct from the last find_pc_sect_line above.  */
  > +	  sal.pc = MSYMBOL_VALUE_ADDRESS (objfile, msymbol);
  > +	  sal.pc = gdbarch_convert_from_func_ptr_addr (gdbarch, sal.pc,
  > +						       &current_target);
  > +	}
  > +      else
  > +	skip_prologue_sal (&sal);
  > +    }
  >
  >    if (maybe_add_address (self->addr_set, objfile->pspace, sal.pc))
  >      add_sal_to_sals (self, result, &sal, MSYMBOL_NATURAL_NAME  
(msymbol), 0);
  > diff --git a/gdb/symtab.c b/gdb/symtab.c
  > index 6693930..43840ab 100644
  > --- a/gdb/symtab.c
  > +++ b/gdb/symtab.c
  > @@ -3617,6 +3617,13 @@ find_function_start_sal (struct symbol *sym, int  
funfirstline)
  >    section = SYMBOL_OBJ_SECTION (symbol_objfile (sym), sym);
  >    sal = find_pc_sect_line (BLOCK_START (SYMBOL_BLOCK_VALUE (sym)),  
section, 0);
  >
  > +  if (funfirstline && sal.symtab != NULL
  > +      && COMPUNIT_LOCATIONS_VALID (SYMTAB_COMPUNIT (sal.symtab)))
  > +    {
  > +      sal.pc = BLOCK_START (SYMBOL_BLOCK_VALUE (sym));
  > +      return sal;
  > +    }
  > +
  >    /* We always should have a line for the function start address.
  >       If we don't, something is odd.  Create a plain SAL refering
  >       just the PC and hope that skip_prologue_sal (if requested)

[patchv2] Do not skip prologue for asm (.S) files

[Jan Kratochvil]

[-- Attachment #1: Type: text/plain, Size: 509 bytes --]

Hi Doug,

Sergio has found a regression on ppc64 so I had to patch another function.
Now on ppc64:

+Running /root/jkratoch/redhat/gdb-clean/gdb/testsuite/gdb.arch/amd64-prologue-skip.exp ...
-PASS: gdb.base/break.exp: run until function breakpoint, optimized file
+PASS: gdb.base/break.exp: run until function breakpoint, optimized file (code motion)
-PASS: gdb.threads/attach-many-short-lived-threads.exp: iter 3: attach
+XFAIL: gdb.threads/attach-many-short-lived-threads.exp: iter 3: attach (EPERM)


Jan

[-- Attachment #2: 1 --]
[-- Type: text/plain, Size: 5458 bytes --]

gdb/ChangeLog
2015-06-25  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* dwarf2read.c (process_full_comp_unit): Set LOCATIONS_VALID also for
	language_asm.
	* linespec.c (minsym_found): Reset sal.PC for COMPUNIT_LOCATIONS_VALID.
	* symtab.c (find_function_start_sal): Likewise.

gdb/testsuite/ChangeLog
2015-06-20  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* gdb.arch/amd64-prologue-skip.S: New file.
	* gdb.arch/amd64-prologue-skip.exp: New file.

diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 496b74f..8bfd034 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -8094,7 +8094,7 @@ process_full_comp_unit (struct dwarf2_per_cu_data *per_cu,
 	 Still one can confuse GDB by using non-standard GCC compilation
 	 options - this waits on GCC PR other/32998 (-frecord-gcc-switches).
 	 */ 
-      if (cu->has_loclist && gcc_4_minor >= 5)
+      if ((cu->has_loclist && gcc_4_minor >= 5) || cu->language == language_asm)
 	cust->locations_valid = 1;
 
       if (gcc_4_minor >= 5)
diff --git a/gdb/linespec.c b/gdb/linespec.c
index d2089b5..e5b4c56 100644
--- a/gdb/linespec.c
+++ b/gdb/linespec.c
@@ -3454,7 +3454,22 @@ minsym_found (struct linespec_state *self, struct objfile *objfile,
     sal = find_pc_sect_line (pc, NULL, 0);
 
   if (self->funfirstline)
-    skip_prologue_sal (&sal);
+    {
+      if (sal.symtab != NULL
+	  && COMPUNIT_LOCATIONS_VALID (SYMTAB_COMPUNIT (sal.symtab)))
+	{
+	  /* If gdbarch_convert_from_func_ptr_addr does not apply then
+	     sal.SECTION, sal.LINE&co. will stay correct from above.
+	     If gdbarch_convert_from_func_ptr_addr applies then
+	     sal.SECTION is cleared from above and sal.LINE&co. will
+	     stay correct from the last find_pc_sect_line above.  */
+	  sal.pc = MSYMBOL_VALUE_ADDRESS (objfile, msymbol);
+	  sal.pc = gdbarch_convert_from_func_ptr_addr (gdbarch, sal.pc,
+						       &current_target);
+	}
+      else
+	skip_prologue_sal (&sal);
+    }
 
   if (maybe_add_address (self->addr_set, objfile->pspace, sal.pc))
     add_sal_to_sals (self, result, &sal, MSYMBOL_NATURAL_NAME (msymbol), 0);
diff --git a/gdb/symtab.c b/gdb/symtab.c
index 6693930..43840ab 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -3617,6 +3617,13 @@ find_function_start_sal (struct symbol *sym, int funfirstline)
   section = SYMBOL_OBJ_SECTION (symbol_objfile (sym), sym);
   sal = find_pc_sect_line (BLOCK_START (SYMBOL_BLOCK_VALUE (sym)), section, 0);
 
+  if (funfirstline && sal.symtab != NULL
+      && COMPUNIT_LOCATIONS_VALID (SYMTAB_COMPUNIT (sal.symtab)))
+    {
+      sal.pc = BLOCK_START (SYMBOL_BLOCK_VALUE (sym));
+      return sal;
+    }
+
   /* We always should have a line for the function start address.
      If we don't, something is odd.  Create a plain SAL refering
      just the PC and hope that skip_prologue_sal (if requested)
diff --git a/gdb/testsuite/gdb.arch/amd64-prologue-skip.S b/gdb/testsuite/gdb.arch/amd64-prologue-skip.S
new file mode 100644
index 0000000..66b806a
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/amd64-prologue-skip.S
@@ -0,0 +1,28 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2015 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+	.text
+/*0*/	hlt
+pushrbp: .globl pushrbp
+#define PUSHRBP push %rbp; mov %rsp, %rbp; nop
+/*1*/	PUSHRBP
+/*6*/	hlt
+
+/*7*/	hlt
+#define MINSYM nop; .globl minsym; minsym: nop
+/*8*/	MINSYM
+/*a*/	hlt
diff --git a/gdb/testsuite/gdb.arch/amd64-prologue-skip.exp b/gdb/testsuite/gdb.arch/amd64-prologue-skip.exp
new file mode 100644
index 0000000..015cd69
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/amd64-prologue-skip.exp
@@ -0,0 +1,35 @@
+# Copyright 2010-2015 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+standard_testfile .S
+set binfile ${binfile}.o
+
+if { ![istarget x86_64-*-* ] || ![is_lp64_target] } {
+    verbose "Skipping ${testfile}."
+    return
+}
+
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" object {debug}] != "" } {
+    untested ${testfile}
+    return
+}
+
+clean_restart ${binfile}
+
+gdb_test "break *pushrbp" " at 0x1: file .*"
+gdb_test "break pushrbp" " at 0x1: file .*"
+
+gdb_test "break *minsym" " at 0x9: file .*"
+gdb_test "break minsym" " at 0x9: file .*"