[ELF] - Report LMA region overflows.

We do not report LMA region overflows currently.
Both GNU linkers do that. The patch implements it.

Differential revision: https://reviews.llvm.org/D44094

llvm-svn: 326892

lld/ELF/LinkerScript.cpp

@@ -117,9 +117,9 @@ void LinkerScript::expandOutputSection(uint64_t Size) {
   if (Ctx->MemRegion)
     expandMemoryRegion(Ctx->MemRegion, Size, Ctx->MemRegion->Name,
                        Ctx->OutSec->Name);
-  // FIXME: check LMA region overflow too.
   if (Ctx->LMARegion)
-    Ctx->LMARegion->CurPos += Size;
+    expandMemoryRegion(Ctx->LMARegion, Size, Ctx->LMARegion->Name,
+                       Ctx->OutSec->Name);
 }
 
 void LinkerScript::setDot(Expr E, const Twine &Loc, bool InSec) {

lld/test/ELF/linkerscript/lma-overflow.test

@@ -0,0 +1,17 @@
+# REQUIRES: x86
+
+# echo '.section .foo,"a"; .quad 1' | llvm-mc -filetype=obj -triple=x86_64-unknown-linux - -o %t.o
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %t.s -o %t.o
+# RUN: not ld.lld -o %t %t.o --script %s 2>&1 | FileCheck %s
+# CHECK: error: section '.foo' will not fit in region 'flash': overflowed by 264 bytes
+
+MEMORY {
+  ram (rwx) : org = 0x1000, len = 0x300
+  flash (rwx) : org = 0x1000, len = 0x100
+}
+SECTIONS {
+  .foo : {
+    *(.foo)
+    . += 0x200;
+  } > ram AT>flash
+}