6 files changed, 100 insertions, 9 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 2fef7d2..0ad7576 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,15 @@
 2019-07-09  Andrew Burgess  <andrew.burgess@embecosm.com>
 
+	* linespec.c (decode_digits_list_mode): Set explicit_line to a
+	bool value.
+	(decode_digits_ordinary): Set explicit_line field in sal.
+	* symtab.c (skip_prologue_sal): Don't skip prologue for a
+	symtab_and_line that was set on an explicit line number in
+	assembler code.  Do always update the recorded symtab and line if
+	we do skip the prologue.
+
+2019-07-09  Andrew Burgess  <andrew.burgess@embecosm.com>
+
 	* breakpoint.c (set_breakpoint_location_function): Remove
 	explicit_loc parameter.
 	(momentary_breakpoint_from_master): Update call to
diff --git a/gdb/linespec.c b/gdb/linespec.c
index 8db3924..83468f8 100644
--- a/gdb/linespec.c
+++ b/gdb/linespec.c
@@ -4101,7 +4101,7 @@ decode_digits_list_mode (struct linespec_state *self,
 	val.symtab = elt;
       val.pspace = SYMTAB_PSPACE (elt);
       val.pc = 0;
-      val.explicit_line = 1;
+      val.explicit_line = true;
 
       add_sal_to_sals (self, &values, &val, NULL, 0);
     }
@@ -4135,6 +4135,7 @@ decode_digits_ordinary (struct linespec_state *self,
 	  sal.pspace = SYMTAB_PSPACE (elt);
 	  sal.symtab = elt;
 	  sal.line = line;
+	  sal.explicit_line = true;
 	  sal.pc = pc;
 	  sals.push_back (std::move (sal));
 	}
diff --git a/gdb/symtab.c b/gdb/symtab.c
index 4920d94..6e7e32f 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -3673,8 +3673,10 @@ skip_prologue_using_lineinfo (CORE_ADDR func_addr, struct symtab *symtab)
 
 /* Adjust SAL to the first instruction past the function prologue.
    If the PC was explicitly specified, the SAL is not changed.
-   If the line number was explicitly specified, at most the SAL's PC
-   is updated.  If SAL is already past the prologue, then do nothing.  */
+   If the line number was explicitly specified then the SAL can still be
+   updated, unless the language for SAL is assembler, in which case the SAL
+   will be left unchanged.
+   If SAL is already past the prologue, then do nothing.  */
 
 void
 skip_prologue_sal (struct symtab_and_line *sal)
@@ -3693,6 +3695,15 @@ skip_prologue_sal (struct symtab_and_line *sal)
   if (sal->explicit_pc)
     return;
 
+  /* In assembly code, if the user asks for a specific line then we should
+     not adjust the SAL.  The user already has instruction level
+     visibility in this case, so selecting a line other than one requested
+     is likely to be the wrong choice.  */
+  if (sal->symtab != nullptr
+      && sal->explicit_line
+      && SYMTAB_LANGUAGE (sal->symtab) == language_asm)
+    return;
+
   scoped_restore_current_pspace_and_thread restore_pspace_thread;
 
   switch_to_program_space_and_thread (sal->pspace);
@@ -3812,12 +3823,6 @@ skip_prologue_sal (struct symtab_and_line *sal)
 
   sal->pc = pc;
   sal->section = section;
-
-  /* Unless the explicit_line flag was set, update the SAL line
-     and symtab to correspond to the modified PC location.  */
-  if (sal->explicit_line)
-    return;
-
   sal->symtab = start_sal.symtab;
   sal->line = start_sal.line;
   sal->end = start_sal.end;
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index f8ef540..a7d09cb 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-07-09  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* gdb.arch/amd64-break-on-asm-line.S: New file.
+	* gdb.arch/amd64-break-on-asm-line.exp: New file.
+
 2019-07-08  Philippe Waroquiers  <philippe.waroquiers@skynet.be>
 
 	* gdb.base/printcmds.exp: Test printing C string and
diff --git a/gdb/testsuite/gdb.arch/amd64-break-on-asm-line.S b/gdb/testsuite/gdb.arch/amd64-break-on-asm-line.S
new file mode 100644
index 0000000..141f71f
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/amd64-break-on-asm-line.S
@@ -0,0 +1,35 @@
+/* Copyright 2019 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/>.
+
+   This file is part of the gdb testsuite.
+
+   Test that a breakpoint placed by line number in an assembler file
+   will stop at the specified line.  Previously versions of GDB have
+   incorrectly invoked the prologue analysis logic and skipped
+   forward.  */
+
+	.text
+	.global main
+main:
+	nop
+test:
+	/* The next two instructions are required to look like an
+	   x86-64 prologue so that GDB's prologue scanner will spot
+	   them and skip forward.  */
+	push    %rbp		/* Break here.  */
+	mov	%rsp, %rbp
+	nop			/* Incorrect.  */
+	nop
+	nop
diff --git a/gdb/testsuite/gdb.arch/amd64-break-on-asm-line.exp b/gdb/testsuite/gdb.arch/amd64-break-on-asm-line.exp
new file mode 100644
index 0000000..6218ce5
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/amd64-break-on-asm-line.exp
@@ -0,0 +1,35 @@
+# Copyright 2019 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/>.
+
+if { ![istarget x86_64-*-* ] || ![is_lp64_target] } {
+    return
+}
+
+standard_testfile .S
+
+if { [prepare_for_testing "failed to prepare" ${testfile} ${srcfile} \
+	  { debug }] } {
+    untested "could not compile"
+    return -1
+}
+
+if ![runto_main] {
+    untested "could not run to main"
+    return -1
+}
+
+gdb_breakpoint [gdb_get_line_number "Break here"]
+gdb_continue_to_breakpoint "Break on specified line" \
+    ".*/\\* Break here\\.  \\*/.*"