From 88b828e2532e11d6bb309cdc39df08445b5debca Mon Sep 17 00:00:00 2001
From: Adrian Prantl <aprantl@apple.com>
Date: Tue, 22 Aug 2017 01:10:48 +0000
Subject: [PATCH] dsymutil: don't copy compile units without children from PCM
 files

rdar://problem/33830532

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311416 91177308-0d34-0410-b5e6-96231b3b80d8
---
 test/tools/dsymutil/Inputs/modules-empty/1.o  | Bin 0 -> 2176 bytes
 .../dsymutil/Inputs/modules-empty/Empty.pcm   | Bin 0 -> 1304 bytes
 test/tools/dsymutil/X86/modules-empty.m       |  28 ++++++++++++++++++
 tools/dsymutil/DwarfLinker.cpp                |   2 ++
 4 files changed, 30 insertions(+)
 create mode 100644 test/tools/dsymutil/Inputs/modules-empty/1.o
 create mode 100644 test/tools/dsymutil/Inputs/modules-empty/Empty.pcm
 create mode 100644 test/tools/dsymutil/X86/modules-empty.m

diff --git a/test/tools/dsymutil/Inputs/modules-empty/1.o b/test/tools/dsymutil/Inputs/modules-empty/1.o
new file mode 100644
index 0000000000000000000000000000000000000000..19588357e77a0a1f9248a992b1f788b9b049ea15
GIT binary patch
literal 2176
zcmb7G%TE(w5TEU~fE1P@A`p%CfC^Dd35~`_q(#tbOf-l>qUK}UE~VJrHhmx%42=h)
zo;({598F9_Z(dAHJP=R(3!2Euc=F~8XLe_y-Ijn8=9~FuXMQvDy~^s(?|<t7BpGl(
zb|d>eG$12&A-^Q!7UZEoq%g%G*>l7MVug%ILKL*Qf~8yYv5|?f&AF|$utInhY28q=
zeMkzCiOs}CN>`Iw%9zRsF&r6-Y<k!@4Q#r~^=*29uS`e0gcd6%MZS<T&4@Q18NIOK
z(!tsk%kgSF*M>7HHl7-b<+NFvSK>Wj=OoMbJH(@2Da48Qm2sZ3?5?wvC@ugOR<pjG
zY9zIMHJ(9-p^RQLUYV&Tp038t5}ozgcsA_zcxpDA)`X$zR9;oT83sDb1ubt|pM^)K
zhC-b6y<)s>#{0HIJhQ&68h7HYI`CTPGE|ad{jB;5^VypH{$RX|j4`k+UOb~?T?J7z
z?xl=`5LbrF(}y{`pN%ENqpLiD=Y>-_>eHshR1SB;3J{|5{!X%YnDLevkEh@Tn6`D2
z_Wekw3=`40eoKtU>EJW>JGn)Dv~T8xZfZ2sP<SWuH2cq?#6PM7t|6Bb^~*h%n|Gw&
zh(1~C|FAOho4oIQq%n*fPvgDv&uY1RDr5Lh1cHH}zo(EZ8h8Bz{r$nvK(D_iou1YE
z%50%t&@+i*TFW0V8pXVp2<XrUBYL(l4*}5ClmRKDU>O40xQ<1)N{5s-kF5AQ_9<(N
z-d1Th9$VJ|kd@Mc@^AqkU%3HJd(U_~+weIJ06By^Wra+a+6M7)_jIH4Ij<MjrLGk=
z(Y`Epy&bB5GeqzAZDcnxuAsS0J~(O40HP>)qX6j1bzR1R)|bA>Qu|R9RwyduAl)3L
zaqk3<o^cx7a2N&So43vfghB{}6k1t+@h&xZ>K5t{y&j3$+eNa8j7XNvy0bHj&lirN
z%}j)HkQ|W8V`=V;T}S#~AIiIjz>w(rNKl8;gYD2k0|=HLdqXIxQ}U&@>8Mr_|6Y+#
z1=--z{ZWwSe3GxJzTp{q5y*bz(jO{&eVyY0B8u;k>wL4d6ad5M<ANhNO42W-8Apk7
zAWPM!4L<<v+SpLJUGm6{pIk1CqW=S2fTySi4n>9O3!b5aEK!(qYM$(rw1ozngn6Lh
EAL^y$BLDyZ

literal 0
HcmV?d00001

diff --git a/test/tools/dsymutil/Inputs/modules-empty/Empty.pcm b/test/tools/dsymutil/Inputs/modules-empty/Empty.pcm
new file mode 100644
index 0000000000000000000000000000000000000000..a1de19eae746f1b24bcf550c77ec73d966004a73
GIT binary patch
literal 1304
zcmX^A>+L^w1_nlE1|R{%Oh9}B#8CiZAdm#&9UwjqU;xqt1TUa!V0@sN3?R%6k_3YI
z_>$C$5(pc@4{?nMLGaO8F!PYa8<5yQ^HNfiO4H+uONzk4@$oL<jzMn7O2BMKs0bGG
zKwgCdn0bjwNkyq;Aorr02Qx<)szZ|nt`)|>YF=huT0Tetx_L0Kt3h?!5NTdfVqSV`
zF{XJ{Fjqk7BqGhrO-u$m5#4<-^PthoK-j#*f`XjX_`Jkikn=G7TMc!W3Y1PJ=st*f
z`AJ#HAT8+bn~!E*JCWvr-B*y9jBegxH1k#yX<kWX0apJ$hnlAYrOy*I50aj9GV@YF
zTF~7m42=j`sCmB$n5P0%Cje5*!v)rnoC8ca3T3H9#hLke3TAo+dIky_B}Juq*$T#n
zhQ?;5nhF{@Ic2%}2r&y|O$OK8f|5$T3<iA$MnMKuK4Dg7J^^uQzKu?xysZSp5NB|J
zT_?a`4z`Pd!5&DP9A7_YN2a|cgGaEV2S^^4lz5<uAYyC`|ABy3YDA!Rfl4Pv1~vv}
e23DYxxxsdViZ&(&P=;n?{LRM;BpIR31X2Jl$de8L

literal 0
HcmV?d00001

diff --git a/test/tools/dsymutil/X86/modules-empty.m b/test/tools/dsymutil/X86/modules-empty.m
new file mode 100644
index 00000000000..3d95aa16880
--- /dev/null
+++ b/test/tools/dsymutil/X86/modules-empty.m
@@ -0,0 +1,28 @@
+/* Compile with:
+   cat >modules.modulemap <<EOF
+     module Empty {
+       header "Empty.h"
+     }
+EOF
+   touch Empty.h
+   clang -c -fmodules -fmodule-map-file=modules.modulemap \
+     -g -gmodules -fmodules-cache-path=. \
+     -Xclang -fdisable-module-hash modules-empty.m -o 1.o
+*/
+
+// RUN: rm -rf %t.dir
+// RUN: mkdir %t.dir
+// RUN: cp %p/../Inputs/modules-empty/1.o %p/../Inputs/modules-empty/Empty.pcm %t.dir
+// RUN: llvm-dsymutil -f -oso-prepend-path=%t.dir \
+// RUN:   -y %p/dummy-debug-map.map -o - \
+// RUN:     | llvm-dwarfdump --debug-dump=info - | FileCheck %s
+
+#include "Empty.h"
+int main() {
+  return 0;
+}
+
+// The empty CU from the pcm should not get copied into the dSYM.
+// CHECK: DW_TAG_compile_unit
+// CHECK-NOT: DW_TAG_compile_unit
+
diff --git a/tools/dsymutil/DwarfLinker.cpp b/tools/dsymutil/DwarfLinker.cpp
index f9328e42fd0..6b5415a0795 100644
--- a/tools/dsymutil/DwarfLinker.cpp
+++ b/tools/dsymutil/DwarfLinker.cpp
@@ -3358,6 +3358,8 @@ void DwarfLinker::loadClangModule(StringRef Filename, StringRef ModulePath,
       Unit->markEverythingAsKept();
     }
   }
+  if (!Unit->getOrigUnit().getUnitDIE().hasChildren())
+    return;
   if (Options.Verbose) {
     outs().indent(Indent);
     outs() << "cloning .debug_info from " << Filename << "\n";
-- 
2.50.1