From 7ab35c6265425a81c14bc313eb4c834985a73ddb Mon Sep 17 00:00:00 2001
From: Michael Matz <matz@suse.de>
Date: Mon, 3 Oct 2016 19:21:10 +0200
Subject: [PATCH] struct-init: Copy relocs for compound literals

When copying the content of compound literals we must
include relocations as well.
---
 tccgen.c                      | 26 ++++++++++++++++++++++++++
 tests/tests2/86-struct-init.c | 29 +++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+)

diff --git a/tccgen.c b/tccgen.c
index f9d4a7c..79ec789 100644
--- a/tccgen.c
+++ b/tccgen.c
@@ -5995,9 +5995,35 @@ static void init_putv(CType *type, Section *sec, unsigned long c)
 	    /* These come from compound literals, memcpy stuff over.  */
 	    Section *ssec;
 	    ElfW(Sym) *esym;
+	    ElfW_Rel *rel;
 	    esym = &((ElfW(Sym) *)symtab_section->data)[vtop->sym->c];
 	    ssec = tcc_state->sections[esym->st_shndx];
 	    memmove (ptr, ssec->data + esym->st_value, size);
+	    if (ssec->reloc) {
+		/* We need to copy over all memory contents, and that
+		   includes relocations.  Use the fact that relocs are
+		   created it order, so look from the end of relocs
+		   until we hit one before the copied region.  */
+		int num_relocs = ssec->reloc->data_offset / sizeof(*rel);
+		rel = (ElfW_Rel*)(ssec->reloc->data + ssec->reloc->data_offset);
+		while (num_relocs--) {
+		    rel--;
+		    if (rel->r_offset >= esym->st_value + size)
+		      continue;
+		    if (rel->r_offset < esym->st_value)
+		      break;
+		    put_elf_reloca(symtab_section, sec,
+				   c + rel->r_offset - esym->st_value,
+				   ELFW(R_TYPE)(rel->r_info),
+				   ELFW(R_SYM)(rel->r_info),
+#if defined(TCC_TARGET_ARM64) || defined(TCC_TARGET_X86_64)
+				   rel->r_addend
+#else
+				   0
+#endif
+				  );
+		}
+	    }
 	} else {
 	    if ((vtop->r & VT_SYM) &&
 		(bt == VT_BYTE ||
diff --git a/tests/tests2/86-struct-init.c b/tests/tests2/86-struct-init.c
index 3cf25c7..8d27719 100644
--- a/tests/tests2/86-struct-init.c
+++ b/tests/tests2/86-struct-init.c
@@ -109,6 +109,21 @@ struct pkthdr {
     struct in6_addr daddr, saddr;
 };
 struct pkthdr phdr = { { { 6,5,4,3 } }, { { 9,8,7,6 } } };
+
+struct Wrap {
+    void *func;
+};
+int global;
+void inc_global (void)
+{
+  global++;
+}
+
+struct Wrap global_wrap[] = {
+    ((struct Wrap) {inc_global}),
+    inc_global,
+};
+
 #include <stdio.h>
 void print_ (const char *name, const u8 *p, long size)
 {
@@ -171,6 +186,19 @@ void foo (struct W *w, struct pkthdr *phdr_)
 }
 #endif
 
+void test_compound_with_relocs (void)
+{
+  struct Wrap local_wrap[] = {
+      ((struct Wrap) {inc_global}),
+      inc_global,
+  };
+  void (*p)(void);
+  p = global_wrap[0].func; p();
+  p = global_wrap[1].func; p();
+  p = local_wrap[0].func; p();
+  p = local_wrap[1].func; p();
+}
+
 int main()
 {
   print(ce);
@@ -195,5 +223,6 @@ int main()
   print(phdr);
   foo(&gw, &phdr);
   //printf("q: %s\n", q);
+  test_compound_with_relocs();
   return 0;
 }