guix: Remove now-unnecessary gcc make flag

[dongcarl]

Previously, Guix would produce a gcc which did not know to use the SSP
function from glibc, and required a gcc make flag for it to do so, in my
attempt to fix it upstream I realized that this is no longer the case.

This can be verified by performing a Guix build and doing

  readelf -s ... | grep __stack_chk

to check that symbols are coming from glibc, and doing

  readelf -d ... | grep NEEDED | grep ssp

to see that libssp.so is not being depended on

[practicalswift]

Concept ACK

Nice 8 percent reduction of manifest.scm: less is more.

Very exciting to follow your excellent guix work. Keep trucking!

[fanquake]

ACK 0ae42a1 - ran a Guix build (hashes below) and checked all the linux binaries:

# Linux-x86-64:
llvm-readelf -s bitcoind | grep __stack_chk
   183: 0000000000000000     0 FUNC    GLOBAL DEFAULT  UND __stack_chk_fail@GLIBC_2.4
llvm-readelf -d bitcoind | grep NEEDED
  0x0000000000000001 (NEEDED)             Shared library: [libpthread.so.0]
  0x0000000000000001 (NEEDED)             Shared library: [librt.so.1]
  0x0000000000000001 (NEEDED)             Shared library: [libm.so.6]
  0x0000000000000001 (NEEDED)             Shared library: [libgcc_s.so.1]
  0x0000000000000001 (NEEDED)             Shared library: [libc.so.6]
  0x0000000000000001 (NEEDED)             Shared library: [ld-linux-x86-64.so.2]

# RISCV64:
llvm-readelf -s bitcoind | grep __stack_chk
    76: 0000000000000000     0 OBJECT  GLOBAL DEFAULT  UND __stack_chk_guard@GLIBC_2.27
   315: 0000000000000000     0 FUNC    GLOBAL DEFAULT  UND __stack_chk_fail@GLIBC_2.27
llvm-readelf -d bitcoind | grep NEEDED
  0x0000000000000001 (NEEDED)             Shared library: [libpthread.so.0]
  0x0000000000000001 (NEEDED)             Shared library: [libm.so.6]
  0x0000000000000001 (NEEDED)             Shared library: [libgcc_s.so.1]
  0x0000000000000001 (NEEDED)             Shared library: [libc.so.6]
  0x0000000000000001 (NEEDED)             Shared library: [ld-linux-riscv64-lp64d.so.1]
  0x0000000000000001 (NEEDED)             Shared library: [libatomic.so.1]

# arm-linux-gnueabihf:
llvm-readelf -s bitcoind | grep __stack_chk
    55: 00000000     0 OBJECT  GLOBAL DEFAULT  UND __stack_chk_guard@GLIBC_2.4
   202: 00000000     0 FUNC    GLOBAL DEFAULT  UND __stack_chk_fail@GLIBC_2.4
llvm-readelf -d bitcoind | grep NEEDED
  0x00000001 (NEEDED)             Shared library: [libpthread.so.0]
  0x00000001 (NEEDED)             Shared library: [librt.so.1]
  0x00000001 (NEEDED)             Shared library: [libm.so.6]
  0x00000001 (NEEDED)             Shared library: [libgcc_s.so.1]
  0x00000001 (NEEDED)             Shared library: [libc.so.6]
  0x00000001 (NEEDED)             Shared library: [ld-linux-armhf.so.3]

# aarch64:
llvm-readelf -s bitcoind | grep __stack_chk
    56: 0000000000000000     0 FUNC    GLOBAL DEFAULT  UND __stack_chk_fail@GLIBC_2.17
    72: 0000000000000000     0 OBJECT  GLOBAL DEFAULT  UND __stack_chk_guard@GLIBC_2.17
llvm-readelf -d bitcoind | grep NEEDED
  0x0000000000000001 (NEEDED)             Shared library: [libpthread.so.0]
  0x0000000000000001 (NEEDED)             Shared library: [libm.so.6]
  0x0000000000000001 (NEEDED)             Shared library: [libgcc_s.so.1]
  0x0000000000000001 (NEEDED)             Shared library: [libc.so.6]
  0x0000000000000001 (NEEDED)             Shared library: [ld-linux-aarch64.so.1]

env PATH="/root/.config/guix/current/bin${PATH:+:}$PATH" guix describe
guix bf8ee1c
  repository URL: https://git.savannah.gnu.org/git/guix.git
  branch: master
  commit: bf8ee1c5046c7011d641e10277984c9bb7dc7c2f

git rev-parse HEAD
0ae42a16c766a7ecb8711bfad6f22b8581ea0258

find output/ -type f -print0 | sort -z | xargs -r0 sha256sum
69e6566ebb91f03dbe76a5fa02ac214e06f36dacb210346f79e73c0c49324251  output/bitcoin-0.19.99-aarch64-linux-gnu-debug.tar.gz
58b29472d729641d28ed4a9a4561ee8498959cb0c02afaf7b3c62f6523420f85  output/bitcoin-0.19.99-aarch64-linux-gnu.tar.gz
18af2395f088e583833a9b6c13a205df1c762952ecf0e8f3fde5f2e11fc74ca5  output/bitcoin-0.19.99-arm-linux-gnueabihf-debug.tar.gz
712f67727e5d6c8c70639fb3a4bd501aeb97461af31de1adcb63fcf31c777c00  output/bitcoin-0.19.99-arm-linux-gnueabihf.tar.gz
c0945466937ed6a325350c9238b5801970e07c9af158f3f9f1043c8f3c7d2d0a  output/bitcoin-0.19.99-riscv64-linux-gnu-debug.tar.gz
3dbae635bebc6e592ae357b6db19ca226959254ce482ae1b730fee6bc1a8c5d9  output/bitcoin-0.19.99-riscv64-linux-gnu.tar.gz
c17ebf034fe9d3f65039e5b9c01bcd8e8412a433d1a67ff1b540688c028aea2b  output/bitcoin-0.19.99-x86_64-linux-gnu-debug.tar.gz
f26bdc9fd67880c68651bb44b0bb756cdc8fbef4299bc25befff7cd5075f4ee7  output/bitcoin-0.19.99-x86_64-linux-gnu.tar.gz
4a8b0c66ade937e645db9d643559819eb7eceac0cf0b7282bf783d1cf24565b6  output/src/bitcoin-0.19.99.tar.gz