32-bit powerpc graphics/mesa-dri build failure (poudriere based): "error: cannot redeclare builtin function" (e.g., __sync_add_and_fetch_8)

[Mark Millard]

On 2020-Jul-22, at 14:11, Jan Beich <jbeich at FreeBSD.org> wrote:

> Mark Millard via freebsd-ppc <freebsd-ppc at freebsd.org> writes:
> 
>> ../src/util/u_atomic.c:38:1: error: cannot redeclare builtin function '__sync_add_and_fetch_8'
>> __sync_add_and_fetch_8(uint64_t *ptr, uint64_t val)
>> ^
>> ../src/util/u_atomic.c:38:1: note: '__sync_add_and_fetch_8' is a builtin with type 'long long (volatile long long *, long long, ...)'
>> ../src/util/u_atomic.c:38:1: error: definition of builtin function '__sync_add_and_fetch_8'
>> __sync_add_and_fetch_8(uint64_t *ptr, uint64_t val)
>> ^
>> ../src/util/u_atomic.c:51:1: error: cannot redeclare builtin function '__sync_sub_and_fetch_8'
>> __sync_sub_and_fetch_8(uint64_t *ptr, uint64_t val)
>> ^
>> ../src/util/u_atomic.c:51:1: note: '__sync_sub_and_fetch_8' is a builtin with type 'long long (volatile long long *, long long, ...)'
>> ../src/util/u_atomic.c:51:1: error: definition of builtin function '__sync_sub_and_fetch_8'
>> __sync_sub_and_fetch_8(uint64_t *ptr, uint64_t val)
>> ^
>> ../src/util/u_atomic.c:64:1: error: cannot redeclare builtin function '__sync_val_compare_and_swap_8'
>> __sync_val_compare_and_swap_8(uint64_t *ptr, uint64_t oldval, uint64_t newval)
>> ^
>> ../src/util/u_atomic.c:64:1: note: '__sync_val_compare_and_swap_8' is a builtin with type 'long long (volatile long long *, long long, long long, ...)'
>> ../src/util/u_atomic.c:64:1: error: definition of builtin function '__sync_val_compare_and_swap_8'
>> __sync_val_compare_and_swap_8(uint64_t *ptr, uint64_t oldval, uint64_t newval)
>> ^
>> 6 errors generated.
> 
> Try replacing files/patch-i386 with https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5464
> On i386 (clang) one can sometimes avoid -latomic by bumping -march
> (FreeBSD 11.4/12.2/13.0 defaults to i686) but powerpc (gcc) probably
> can't use __sync* with 64-bit types without -latomic, making Meson
> define MISSING_64BIT_ATOMICS to use src/util/u_atomic.c

The context was head (so system-clang instead of
gcc 4.2.1). But, looking in the logs, it seems to
have used an odd mix of system-clang and devel/lvm80
materials:

. . .
Project name: mesa
Project version: 19.0.8
Using 'CC' from environment with value: 'cc'
Using 'CFLAGS' from environment with value: '-O2 -pipe  -g -fstack-protector-strong -fno-strict-aliasing '
Using 'LDFLAGS' from environment with value: ' -Wl,-rpath=/usr/local/llvm80/lib -fstack-protector-strong '
Using 'CPPFLAGS' from environment with value: ''
Using 'CXX' from environment with value: 'c++'
Using 'CXXFLAGS' from environment with value: '-O2 -pipe -g -fstack-protector-strong -fno-strict-aliasing  '
Using 'LDFLAGS' from environment with value: ' -Wl,-rpath=/usr/local/llvm80/lib -fstack-protector-strong '
Using 'CPPFLAGS' from environment with value: ''
Using 'CC' from environment with value: 'cc'
Using 'CFLAGS' from environment with value: '-O2 -pipe  -g -fstack-protector-strong -fno-strict-aliasing '
Using 'LDFLAGS' from environment with value: ' -Wl,-rpath=/usr/local/llvm80/lib -fstack-protector-strong '
Using 'CPPFLAGS' from environment with value: ''
C compiler for the host machine: cc (clang 10.0.1 "FreeBSD clang version 10.0.1 (git at github.com:llvm/llvm-project.git llvmorg-10.0.1-rc2-0-g77d76b71d7d)")
C linker for the host machine: cc ld.lld 10.0.1
Using 'CXX' from environment with value: 'c++'
Using 'CXXFLAGS' from environment with value: '-O2 -pipe -g -fstack-protector-strong -fno-strict-aliasing  '
Using 'LDFLAGS' from environment with value: ' -Wl,-rpath=/usr/local/llvm80/lib -fstack-protector-strong '
Using 'CPPFLAGS' from environment with value: ''
C++ compiler for the host machine: c++ (clang 10.0.1 "FreeBSD clang version 10.0.1 (git at github.com:llvm/llvm-project.git llvmorg-10.0.1-rc2-0-g77d76b71d7d)")
C++ linker for the host machine: c++ ld.lld 10.0.1
Host machine cpu family: ppc
Host machine cpu: powerpc
. . .
llvm-config found: YES (/usr/local/bin/llvm-config80) 8.0.1
Run-time dependency LLVM (modules: amdgpu, asmparser, bitreader, bitwriter, engine, ipo, mcdisassembler, mcjit, native) found: YES 8.0.1
. . .
cc . . . -DHAVE_LLVM=0x0800 -DMESA_LLVM_VERSION_PATCH=1 . . . -c ../src/util/u_atomic.c
. . .


The system-clang devel/llvm80 mix seems to be at
least declaring __sync_add_and_fetch_8 ,
__sync_sub_and_fetch_8 , and
__sync_val_compare_and_swap_8 as builtin,
possibly implicitly.

At this point I'm unclear if:

https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5464

is relevant. The system-clang and devel/llvm80 mix
just does not seem the right kind of thing to be
doing in the build.

===
Mark Millard
marklmi at yahoo.com
( dsl-only.net went
away in early 2018-Mar)