Accept multiple --config options

redhat-rpm-config now adds --config to CFLAGS when the macro
%toolchain is set to clang.  Some packages end up adding CFLAGS
twice to their compiler commands, so we need to patch clang to
allow multiple --config options so that these packages won't
fail to compile.

0001-Driver-Accept-multiple-config-options-if-filenames-a.patch

@@ -0,0 +1,64 @@
+From d970ab63e22eb5918774953da6b99ac27e5832a0 Mon Sep 17 00:00:00 2001
+From: Tom Stellard <tstellar@redhat.com>
+Date: Tue, 16 Jun 2020 11:20:20 -0700
+Subject: [PATCH] Driver: Accept multiple --config options if filenames are the
+ same
+
+Summary:
+We're trying to use the --config options to pass distro specific
+options for Fedora via the CFLAGS variable.  However, some projects
+end up using the CFLAGS variable multiple times in their command line,
+which leads to an error when --config is used.
+
+This patch resolves this issue by allowing more than one --config option
+on the command line as long as the file names are the same.
+
+Reviewers: sepavloff, hfinkel
+
+Reviewed By: sepavloff
+
+Subscribers: cfe-commits, llvm-commits
+
+Tags: #clang
+
+Differential Revision: https://reviews.llvm.org/D81424
+---
+ clang/lib/Driver/Driver.cpp     | 8 ++++++--
+ clang/test/Driver/config-file.c | 5 +++++
+ 2 files changed, 11 insertions(+), 2 deletions(-)
+
+diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
+index 3add665..a8442d2 100644
+--- a/clang/lib/Driver/Driver.cpp
++++ b/clang/lib/Driver/Driver.cpp
+@@ -833,8 +833,12 @@ bool Driver::loadConfigFile() {
+     std::vector<std::string> ConfigFiles =
+         CLOptions->getAllArgValues(options::OPT_config);
+     if (ConfigFiles.size() > 1) {
+-      Diag(diag::err_drv_duplicate_config);
+-      return true;
++      if (!std::all_of(
++              ConfigFiles.begin(), ConfigFiles.end(),
++              [ConfigFiles](std::string s) { return s == ConfigFiles[0]; })) {
++        Diag(diag::err_drv_duplicate_config);
++        return true;
++      }
+     }
+ 
+     if (!ConfigFiles.empty()) {
+diff --git a/clang/test/Driver/config-file.c b/clang/test/Driver/config-file.c
+index 04127d4..fde7260 100644
+--- a/clang/test/Driver/config-file.c
++++ b/clang/test/Driver/config-file.c
+@@ -71,3 +71,8 @@
+ // RUN: %clang --config-system-dir=%S/Inputs/config --config-user-dir=%S/Inputs/config2 --config config-4 -S %s -o /dev/null -v 2>&1 | FileCheck %s -check-prefix CHECK-PRECEDENCE
+ // CHECK-PRECEDENCE: Configuration file: {{.*}}Inputs{{.}}config2{{.}}config-4.cfg
+ // CHECK-PRECEDENCE: -Wall
++
++
++//--- Duplicate --config options are allowed if the value is the same
++// RUN: %clang --config-system-dir=%S/Inputs/config --config-user-dir=%S/Inputs/config2 --config config-4 --config config-4 -S %s -o /dev/null -v 2>&1 | FileCheck %s -check-prefix CHECK-SAME-CONFIG
++// CHECK-SAME-CONFIG: Configuration file: {{.*}}Inputs{{.}}config2{{.}}config-4.cfg
+-- 
+1.8.3.1
+

clang.spec

@@ -4,7 +4,7 @@
 %global min_ver 0
 %global patch_ver 0
 #%%global rc_ver 6
-%global baserelease 4
+%global baserelease 5
 
 %global clang_tools_binaries \
 	%{_bindir}/clang-apply-replacements \
@@ -102,6 +102,7 @@ Patch14:	0001-clang-fix-undefined-behaviour-in-RawComment-getForma.patch
 
 # Not Upstream
 Patch15:	0001-clang-Don-t-install-static-libraries.patch
+Patch16:	0001-Driver-Accept-multiple-config-options-if-filenames-a.patch
 
 BuildRequires:	gcc
 BuildRequires:	gcc-c++
@@ -253,6 +254,7 @@ pathfix.py -i %{__python3} -pn \
 %patch13 -p2 -b .unwind-all
 %patch14 -p2 -b .clangd
 %patch15 -p2 -b .no-install-static
+%patch16 -p2 -b .config-multiple
 
 mv ../%{clang_tools_srcdir} tools/extra
 
@@ -480,6 +482,9 @@ LD_LIBRARY_PATH=%{buildroot}%{_libdir} ninja check-all -C _build || \
 
 %endif
 %changelog
+* Mon Jun 08 2020 Tom Stellard <tstellar@redhat.com> - 10.0.0-5
+- Accept multiple --config options
+
 * Wed Jun  3 2020 Dan Čermák <dan.cermak@cgc-instruments.com> - 10.0.0-4
 - Add symlink to %%{_libdir}/clang/%%{maj_ver} for persistent access to the resource directory accross minor version bumps