[binutils-gdb] gdb: Check for nullptr when computing srcpath

[binutils-gdb] gdb: Check for nullptr when computing srcpath

[Aaron Merey]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=e5da11393a16416afc0c0a1da9914b6424f37fa8

commit e5da11393a16416afc0c0a1da9914b6424f37fa8
Author: Aaron Merey <amerey@redhat.com>
Date:   Thu Feb 27 19:07:01 2020 -0500

    gdb: Check for nullptr when computing srcpath
    
    This fixes a regression caused by commit 0d79cdc494d5:
    
      $ make check TESTS="gdb.dwarf2/dw2-ranges-base.exp"
      [...]
      ERROR: GDB process no longer exists
    
    This error is caused by an abort during the computation of srcpath
    when SYMTAB_DIRNAME (s) == NULL.
    
    Computing srcpath only when SYMTAB_DIRNAME (s) is not NULL fixes this
    error. Also change the condition for calling debuginfod_source_query
    to include whether srcpath could be computed.
    
    gdb/ChangeLog:
    
    2020-02-27  Aaron Merey  <amerey@redhat.com>
    
            * source.c (open_source_file): Check for nullptr when computing
            srcpath.

Diff:
---
 gdb/ChangeLog | 5 +++++
 gdb/source.c  | 4 ++--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index d99c178..ff2172c 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2020-02-27  Aaron Merey  <amerey@redhat.com>
+
+	* source.c (open_source_file): Check for nullptr when computing
+	srcpath.
+
 2020-02-27  Tom Tromey  <tromey@adacore.com>
 
 	* dwarf2/read.c (struct field_info) <nfields>: Now a method, not a
diff --git a/gdb/source.c b/gdb/source.c
index 051caf5..50de939 100644
--- a/gdb/source.c
+++ b/gdb/source.c
@@ -1160,7 +1160,7 @@ open_source_file (struct symtab *s)
 	  std::string srcpath;
 	  if (IS_ABSOLUTE_PATH (s->filename))
 	    srcpath = s->filename;
-	  else
+	  else if (SYMTAB_DIRNAME (s) != nullptr)
 	    {
 	      srcpath = SYMTAB_DIRNAME (s);
 	      srcpath += SLASH_STRING;
@@ -1170,7 +1170,7 @@ open_source_file (struct symtab *s)
 	  const struct bfd_build_id *build_id = build_id_bfd_get (ofp->obfd);
 
 	  /* Query debuginfod for the source file.  */
-	  if (build_id != nullptr)
+	  if (build_id != nullptr && !srcpath.empty ())
 	    fd = debuginfod_source_query (build_id->data,
 					  build_id->size,
 					  srcpath.c_str (),