From: Serhei Makarov <serhei@serhei.io>
Date: Fri, 30 Jan 2026 15:50:54 +0000 (-0500)
Subject: src/stackprof.cxx dwfl_module_relocate_address: ship it
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=d7dbd84bb46f71802a46b274060e7e115d57ef92;p=thirdparty%2Felfutils.git

src/stackprof.cxx dwfl_module_relocate_address: ship it

fche was concerned re: whether it works on shared libraries; but
worksforme, and this is the code we need to test, so enabling it.

Without the relocations, not only is the resulting output not
decodable (raw pcs) but systemwide profiles produce a giant histogram.
---

diff --git a/src/stackprof.cxx b/src/stackprof.cxx
index cbb85d24..6c77f926 100644
--- a/src/stackprof.cxx
+++ b/src/stackprof.cxx
@@ -1801,13 +1801,13 @@ void GprofUnwindSampleConsumer::process(const UnwindSample *sample)
   Elf *elf = dwfl_module_getelf (mod, &bias);
   (void)elf;
 #endif
-  
+
   Dwfl_Module *mod2 = dwfl_addrmodule(sample->dwfl, pc2);
   if (mod2 == NULL)
     return;
   // If caller & callee are in different modules, this is a cross-shared-library
   // call, so we can't track it as a call-graph arc.  XXX: at least count them 
-  
+
   // extract buildid for pc (hit callee)
   const unsigned char *desc = nullptr;
   GElf_Addr vaddr;
@@ -1824,9 +1824,10 @@ void GprofUnwindSampleConsumer::process(const UnwindSample *sample)
 
   UnwindModuleStats *buildid_ent = this->stats->buildid_find_or_create(buildid, mod);
 
-  // int i = dwfl_module_relocate_address (mod, &pc);
+  int i = dwfl_module_relocate_address (mod, &pc);
+  (void) i;
   #if 0
-  (void) i; // XXX: for now, ignore relocation-basis section name or whatever
+  // XXX: for now, ignore relocation-basis section name or whatever
   const char *name;
   if (i >= 0)
     name = dwfl_module_relocation_info (mod, i, NULL);
@@ -1835,7 +1836,8 @@ void GprofUnwindSampleConsumer::process(const UnwindSample *sample)
 
   if (mod == mod2) // intra-module call
     {
-      // int j = dwfl_module_relocate_address (mod, &pc2); // map pc2 also
+      int j = dwfl_module_relocate_address (mod, &pc2); // map pc2 also
+      (void) j;
       buildid_ent->record_callgraph_arc(pc2, pc);
     }
 }