llvm@13: drop lldb and use system gcc on Linux

[cho-m]

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[carlocab]

Not too bothered by the scan-build failure. I'm ok to shipping this without scan-build. Though it's possible the failure is indicative of a problem in clang++, which would be a blocker.

[cho-m]

If everything else is fine, then we would need a re-run after dropping scan-build and rebasing.

Not sure if there were any other components that would be worth dropping from versioned LLVM. Removing LLDB at least gets rid of Python linkage and makes llvm@13 last version that can be built with GCC-5.

[carlocab]

scan-build seems to fail with a similar error in #106755.

[iMichka]

This needs to be rebased now that #106755 has been merged.

[cho-m]

We'll need to disable scan-build (at least the test) to avoid failing. Previous run ignored failure since we temporarily dropped bottles.

[carlocab]

So, I guess the question is: is it just scan-build or is something else broken?

[cho-m]

May be worth checking what is happening in background to see what linker is trying to do.

==> /home/linuxbrew/.linuxbrew/Cellar/llvm@13/13.0.1/bin/scan-build clang++ scanbuildtest.cpp 2>&1
  scan-build: Using '/home/linuxbrew/.linuxbrew/Cellar/llvm@13/13.0.1/bin/clang-13' for static analysis
  /home/linuxbrew/.linuxbrew/bin/ld: /tmp/ccLzUtxD.o: in function `main':
  scanbuildtest.cpp:(.text+0xe): undefined reference to `operator new(unsigned long)'
  /home/linuxbrew/.linuxbrew/bin/ld: scanbuildtest.cpp:(.text+0x28): undefined reference to `operator delete(void*)'

[carlocab]

Is there a way to get scan-build to dump verbose logs? e.g. what flags is it passing to the linker?

[cho-m]

Should be able to pass common verbosity flags to compiler command (-v, -Wl,-v).

Output from local run

$ /home/linuxbrew/.linuxbrew/opt/llvm@13/bin/scan-build clang++ -v -Wl,-v test.cpp
scan-build: Using '/home/linuxbrew/.linuxbrew/Cellar/llvm@13/13.0.1_1/bin/clang-13' for static analysis
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/5/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu 5.4.0-6ubuntu1~16.04.12' --with-bugurl=file:///usr/share/doc/gcc-5/README.Bugs --enable-languages=c,ada,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-5 --enable-shared --enable-linker-build-id --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --with-default-libstdcxx-abi=new --enable-gnu-unique-object --disable-vtable-verify --enable-libmpx --enable-plugin --with-system-zlib --disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-5-amd64/jre --enable-java-home --with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-5-amd64 --with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-5-amd64 --with-arch-directory=amd64 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --enable-objc-gc --enable-multiarch --disable-werror --with-arch-32=i686 --with-abi=m64 --with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 5.4.0 20160609 (Ubuntu 5.4.0-6ubuntu1~16.04.12)
COLLECT_GCC_OPTIONS='-v' '-mtune=generic' '-march=x86-64'
 /usr/lib/gcc/x86_64-linux-gnu/5/cc1plus -quiet -v -imultiarch x86_64-linux-gnu -D_GNU_SOURCE test.cpp -quiet -dumpbase test.cpp -mtune=generic -march=x86-64 -auxbase test -version -fstack-protector-strong -Wformat -Wformat-security -o /tmp/ccMefEge.s
GNU C++ (Ubuntu 5.4.0-6ubuntu1~16.04.12) version 5.4.0 20160609 (x86_64-linux-gnu)
	compiled by GNU C version 5.4.0 20160609, GMP version 6.1.0, MPFR version 3.1.4, MPC version 1.0.3
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
ignoring duplicate directory "/usr/include/x86_64-linux-gnu/c++/5"
ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu"
ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux-gnu/5/../../../../x86_64-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/include/c++/5
 /usr/include/x86_64-linux-gnu/c++/5
 /usr/include/c++/5/backward
 /usr/lib/gcc/x86_64-linux-gnu/5/include
 /usr/local/include
 /usr/lib/gcc/x86_64-linux-gnu/5/include-fixed
 /usr/include/x86_64-linux-gnu
 /usr/include
End of search list.
GNU C++ (Ubuntu 5.4.0-6ubuntu1~16.04.12) version 5.4.0 20160609 (x86_64-linux-gnu)
	compiled by GNU C version 5.4.0 20160609, GMP version 6.1.0, MPFR version 3.1.4, MPC version 1.0.3
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 85af4995304287cdd19cfa43cf5d6cf1
COLLECT_GCC_OPTIONS='-v' '-mtune=generic' '-march=x86-64'
 as -v --64 -o /tmp/cceg1LI8.o /tmp/ccMefEge.s
GNU assembler version 2.38 (x86_64-pc-linux-gnu) using BFD version (GNU Binutils) 2.38
COMPILER_PATH=/usr/lib/gcc/x86_64-linux-gnu/5/:/usr/lib/gcc/x86_64-linux-gnu/5/:/usr/lib/gcc/x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/5/:/usr/lib/gcc/x86_64-linux-gnu/
LIBRARY_PATH=/usr/lib/gcc/x86_64-linux-gnu/5/:/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/5/../../../../lib/:/lib/x86_64-linux-gnu/:/lib/../lib/:/usr/lib/x86_64-linux-gnu/:/usr/lib/../lib/:/usr/lib/gcc/x86_64-linux-gnu/5/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-v' '-mtune=generic' '-march=x86-64'
 /usr/lib/gcc/x86_64-linux-gnu/5/collect2 -plugin /usr/lib/gcc/x86_64-linux-gnu/5/liblto_plugin.so -plugin-opt=/usr/lib/gcc/x86_64-linux-gnu/5/lto-wrapper -plugin-opt=-fresolution=/tmp/ccXUNBd3.res -plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lgcc_s -plugin-opt=-pass-through=-lc -plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lgcc_s --sysroot=/ --build-id --eh-frame-hdr -m elf_x86_64 --hash-style=gnu --as-needed -dynamic-linker /lib64/ld-linux-x86-64.so.2 -z relro /usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/crt1.o /usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/crti.o /usr/lib/gcc/x86_64-linux-gnu/5/crtbegin.o -L/usr/lib/gcc/x86_64-linux-gnu/5 -L/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu -L/usr/lib/gcc/x86_64-linux-gnu/5/../../../../lib -L/lib/x86_64-linux-gnu -L/lib/../lib -L/usr/lib/x86_64-linux-gnu -L/usr/lib/../lib -L/usr/lib/gcc/x86_64-linux-gnu/5/../../.. -v /tmp/cceg1LI8.o -lgcc --as-needed -lgcc_s --no-as-needed -lc -lgcc --as-needed -lgcc_s --no-as-needed /usr/lib/gcc/x86_64-linux-gnu/5/crtend.o /usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/crtn.o
collect2 version 5.4.0 20160609
/home/linuxbrew/.linuxbrew/bin/ld -plugin /usr/lib/gcc/x86_64-linux-gnu/5/liblto_plugin.so -plugin-opt=/usr/lib/gcc/x86_64-linux-gnu/5/lto-wrapper -plugin-opt=-fresolution=/tmp/ccXUNBd3.res -plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lgcc_s -plugin-opt=-pass-through=-lc -plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lgcc_s --sysroot=/ --build-id --eh-frame-hdr -m elf_x86_64 --hash-style=gnu --as-needed -dynamic-linker /lib64/ld-linux-x86-64.so.2 -z relro /usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/crt1.o /usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/crti.o /usr/lib/gcc/x86_64-linux-gnu/5/crtbegin.o -L/usr/lib/gcc/x86_64-linux-gnu/5 -L/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu -L/usr/lib/gcc/x86_64-linux-gnu/5/../../../../lib -L/lib/x86_64-linux-gnu -L/lib/../lib -L/usr/lib/x86_64-linux-gnu -L/usr/lib/../lib -L/usr/lib/gcc/x86_64-linux-gnu/5/../../.. -v /tmp/cceg1LI8.o -lgcc --as-needed -lgcc_s --no-as-needed -lc -lgcc --as-needed -lgcc_s --no-as-needed /usr/lib/gcc/x86_64-linux-gnu/5/crtend.o /usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/crtn.o
GNU ld (GNU Binutils) 2.38
/home/linuxbrew/.linuxbrew/bin/ld: /tmp/cceg1LI8.o: in function `main':
test.cpp:(.text+0xe): undefined reference to `operator new(unsigned long)'
/home/linuxbrew/.linuxbrew/bin/ld: test.cpp:(.text+0x28): undefined reference to `operator delete(void*)'
/home/linuxbrew/.linuxbrew/bin/ld: test.cpp:(.text+0x35): undefined reference to `std::cout'
/home/linuxbrew/.linuxbrew/bin/ld: test.cpp:(.text+0x3a): undefined reference to `std::ostream::operator<<(int)'
/home/linuxbrew/.linuxbrew/bin/ld: test.cpp:(.text+0x3f): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::endl<char, std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&)'
/home/linuxbrew/.linuxbrew/bin/ld: test.cpp:(.text+0x47): undefined reference to `std::ostream::operator<<(std::ostream& (*)(std::ostream&))'
/home/linuxbrew/.linuxbrew/bin/ld: /tmp/cceg1LI8.o: in function `__static_initialization_and_destruction_0(int, int)':
test.cpp:(.text+0x75): undefined reference to `std::ios_base::Init::Init()'
/home/linuxbrew/.linuxbrew/bin/ld: test.cpp:(.text+0x84): undefined reference to `std::ios_base::Init::~Init()'
collect2: error: ld returned 1 exit status
scan-build: Analysis run complete.
scan-build: Removing directory '/tmp/scan-build-2022-08-05-160650-18380-1' because it contains no reports.
scan-build: No bugs found.

I think llvm@12 uses #{bin}/clang++ to force Clang compiler. Can reproduce error with llvm@12.

[BrewTestBot]

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