[PATCH] makedumpfile: warn on vmlinux without dwarf

[Cliff Wickman]

From: Cliff Wickman <cpw at sgi.com>

If the vmlinux does not have dwarf information makedumpfile fails in
a rather obscure way, with a flood of redundant errors,

Make it fail with more of a hint of what is wrong.

Signed-off-by: Cliff Wickman <cpw at sgi.com>
---
 dwarf_info.c |    4 ++++
 1 file changed, 4 insertions(+)

Index: makedumpfile.mmap/dwarf_info.c
===================================================================
--- makedumpfile.mmap.orig/dwarf_info.c
+++ makedumpfile.mmap/dwarf_info.c
@@ -139,6 +139,10 @@ process_module (Dwfl_Module *dwflmod,
 
 	/* get a debug context descriptor.*/
 	dwarf_info.dwarfd = dwfl_module_getdwarf (dwflmod, &dwbias);
+	if (dwarf_info.dwarfd == NULL) {
+		fprintf(stderr, "makedumpfile: dwfl_module_getdwarf error\n");
+		exit(1);
+	}
 	dwarf_info.elfd = dwarf_getelf(dwarf_info.dwarfd);
 
 	mod_name = dwfl_module_info(dwflmod, NULL, NULL, NULL, NULL, NULL,