Compilation error

[nmdnm]

Arch Linux

$ git rev-parse HEAD
dc51dc197c1bde688f9502955718edc223168d8f

$ clang++ --version
clang version 10.0.0 
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/bin

$ env CC=clang CXX=clang++ ./build.sh debug
Warning: JAVA_HOME is not set, skipping Java projects
Building debug in out/cmake-debug...
-- The C compiler identification is Clang 10.0.0
-- The CXX compiler identification is Clang 10.0.0
-- Check for working C compiler: /usr/bin/clang
-- Check for working C compiler: /usr/bin/clang - works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/clang++
-- Check for working CXX compiler: /usr/bin/clang++ - works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Looking for pthread.h
-- Looking for pthread.h - found
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD - Failed
-- Check if compiler accepts -pthread
-- Check if compiler accepts -pthread - yes
-- Found Threads: TRUE  
-- The ASM compiler identification is Clang
-- Found assembler: /usr/bin/clang
-- DFG LUT size set to 128x128
-- Found Python3: /usr/bin/python3.8 (found version "3.8.2") found components: Interpreter 
-- Configuring done
-- Generating done
-- Build files have been written to: /home/vikaig/filament/out/cmake-debug
[27/1284] Building CXX object libs/math/CMakeFiles/benchmark_math.dir/benchmarks/benchmark_fast.cpp.o
In file included from ../../libs/math/benchmarks/benchmark_fast.cpp:22:
../../libs/math/include/math/fast.h:132:33: warning: implicit conversion from 'const int' to 'float' changes value from 1064866805 to 1064866816 [-Wimplicit-int-float-conversion]
    u.x = (int)(b * (u.x - K) + K);
                              ~ ^
1 warning generated.
[28/1284] Building CXX object libs/math/CMakeFiles/test_math.dir/tests/test_fast.cpp.o
In file included from ../../libs/math/tests/test_fast.cpp:19:
../../libs/math/include/math/fast.h:132:33: warning: implicit conversion from 'const int' to 'float' changes value from 1064866805 to 1064866816 [-Wimplicit-int-float-conversion]
    u.x = (int)(b * (u.x - K) + K);
                              ~ ^
1 warning generated.
[308/1284] Building CXX object third_party/spirv-tools/source/CMakeFiles/SPIRV-Tools-shared.dir/val/validate.cpp.o
FAILED: third_party/spirv-tools/source/CMakeFiles/SPIRV-Tools-shared.dir/val/validate.cpp.o 
/usr/bin/clang++  -DFILAMENT_DRIVER_SUPPORTS_VULKAN -DSPIRV_CHECK_CONTEXT -DSPIRV_COLOR_TERMINAL -DSPIRV_LINUX -DSPIRV_TIMER_ENABLED -DSPIRV_TOOLS_IMPLEMENTATION -DSPIRV_TOOLS_SHAREDLIB -DSPIRV_Tools_shared_EXPORTS -I../../third_party/spirv-tools -I../../third_party/spirv-tools/include -Ithird_party/spirv-tools -I../../third_party/spirv-tools/external/spirv-headers/include -std=c++14 -fstrict-aliasing -Wno-unknown-pragmas -Wno-unused-function -stdlib=libc++ -fcolor-diagnostics -DTNT_DEV -g -fstack-protector  -fPIC -fvisibility=hidden   -Wextra-semi -Wall -Wextra -Wnon-virtual-dtor -Wno-missing-field-initializers -Wno-self-assign -Werror -std=c++11 -fno-exceptions -fno-rtti -Wno-long-long -Wshadow -Wundef -Wconversion -Wno-sign-conversion -ftemplate-depth=1024 -std=gnu++11 -MD -MT third_party/spirv-tools/source/CMakeFiles/SPIRV-Tools-shared.dir/val/validate.cpp.o -MF third_party/spirv-tools/source/CMakeFiles/SPIRV-Tools-shared.dir/val/validate.cpp.o.d -o third_party/spirv-tools/source/CMakeFiles/SPIRV-Tools-shared.dir/val/validate.cpp.o -c ../../third_party/spirv-tools/source/val/validate.cpp
../../third_party/spirv-tools/source/val/validate.cpp:145:21: error: loop variable 'other_id_name' of type 'const std::__1::basic_string<char>' creates a copy from type 'const std::__1::basic_string<char>' [-Werror,-Wrange-loop-construct]
    for (const auto other_id_name : other_id_names) {
                    ^
../../third_party/spirv-tools/source/val/validate.cpp:145:10: note: use reference type 'const std::__1::basic_string<char> &' to prevent copying
    for (const auto other_id_name : other_id_names) {
         ^~~~~~~~~~~~~~~~~~~~~~~~~~
                    &
../../third_party/spirv-tools/source/val/validate.cpp:434:19: error: loop variable 'inst' of type 'const spvtools::val::Instruction' creates a copy from type 'const spvtools::val::Instruction' [-Werror,-Wrange-loop-construct]
  for (const auto inst : vstate->ordered_instructions()) {
                  ^
../../third_party/spirv-tools/source/val/validate.cpp:434:8: note: use reference type 'const spvtools::val::Instruction &' to prevent copying
  for (const auto inst : vstate->ordered_instructions()) {
       ^~~~~~~~~~~~~~~~~
                  &
2 errors generated.
[310/1284] Building CXX object third_party/spirv-tools/source/CMakeFiles/SPIRV-Tools-shared.dir/val/validate_annotation.cpp.o
ninja: build stopped: subcommand failed.

[kpeeters]

This needs to be const auto& or auto.

[nmdnm]

Compilation is ok with this patch

diff --git a/third_party/spirv-tools/source/val/validate.cpp b/third_party/spirv-tools/source/val/validate.cpp
index 7f4b0dc..7c743c4 100644
--- a/third_party/spirv-tools/source/val/validate.cpp
+++ b/third_party/spirv-tools/source/val/validate.cpp
@@ -142,7 +142,7 @@ spv_result_t ValidateEntryPointNameUnique(ValidationState_t& _,
   for (const auto other_id : _.entry_points()) {
     if (other_id == id) continue;
     const auto other_id_names = CalculateNamesForEntryPoint(_, other_id);
-    for (const auto other_id_name : other_id_names) {
+    for (auto other_id_name : other_id_names) {
       if (names.find(other_id_name) != names.end()) {
         return _.diag(SPV_ERROR_INVALID_BINARY, _.FindDef(id))
                << "Entry point name \"" << other_id_name
@@ -431,7 +431,7 @@ spv_result_t ValidateBinaryUsingContextAndValidationState(
   if (auto error = ValidateBuiltIns(*vstate)) return error;
   // These checks must be performed after individual opcode checks because
   // those checks register the limitation checked here.
-  for (const auto inst : vstate->ordered_instructions()) {
+  for (auto inst : vstate->ordered_instructions()) {
     if (auto error = ValidateExecutionLimitations(*vstate, &inst)) return error;
     if (auto error = ValidateSmallTypeUses(*vstate, &inst)) return error;
   }
diff --git a/third_party/spirv-tools/source/val/validation_state.cpp b/third_party/spirv-tools/source/val/validation_state.cpp
index 51aebbe..281c34d 100644
--- a/third_party/spirv-tools/source/val/validation_state.cpp
+++ b/third_party/spirv-tools/source/val/validation_state.cpp
@@ -1052,7 +1052,7 @@ void ValidationState_t::ComputeFunctionToEntryPointMapping() {
 }
 
 void ValidationState_t::ComputeRecursiveEntryPoints() {
-  for (const Function func : functions()) {
+  for (auto func : functions()) {
     std::stack<uint32_t> call_stack;
     std::set<uint32_t> visited;

[romainguy]

Pending fix in #2562

[romainguy]

I merged the fix from #2562