[Bug target/80881] [7/8 Regression] null pointer access in libgomp.h

["lh_mouse at 126 dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80881

--- Comment #11 from Liu Hao <lh_mouse at 126 dot com> ---
Diff'ing configure options used to build both GCC produces the following
result:

```
E:\Desktop>gcc-7.1.0-debug-broken-tls\bin\gcc.exe -v 2>&1 | sed "s/ --/\n&/g" >
yours.txt

E:\Desktop>gcc -v 2>&1 | sed "s/ --/\n&/g" > mine.txt

E:\Desktop>gcc-7.1.0-debug-broken-tls\bin\gcc.exe -v 2>&1 | sed "s/ --/\n&/g" >
yours.txt

E:\Desktop>diff --color -U1 mine.txt yours.txt
--- mine.txt    2017-11-30 09:42:33.612869600 +0800
+++ yours.txt   2017-11-30 09:42:35.493977200 +0800
@@ -1,47 +1,35 @@
 Using built-in specs.
-COLLECT_GCC=gcc
-COLLECT_LTO_WRAPPER=C:/MinGW/MSYS2/mingw64/lib/gcc/x86_64-w64-mingw32/7.2.1/lto-wrapper.exe
+COLLECT_GCC=gcc-7.1.0-debug-broken-tls\bin\gcc.exe
+COLLECT_LTO_WRAPPER=e:/desktop/gcc-7.1.0-debug-broken-tls/bin/../libexec/gcc/x86_64-w64-mingw32/7.1.0/lto-wrapper.exe
 Target: x86_64-w64-mingw32
-Configured with: ../gcc/configure
- --prefix=/mingw64
- --with-local-prefix=/mingw64/local
- --build=x86_64-w64-mingw32
+Configured with: ../../src/gcc-7.1.0/configure
  --host=x86_64-w64-mingw32
- --target=x86_64-w64-mingw32
- --with-native-system-header-dir=/mingw64/x86_64-w64-mingw32/include
- --libexecdir=/mingw64/lib
- --enable-bootstrap
- --with-arch=x86-64
- --with-tune=nocona
- --enable-languages=c,lto,c++
- --enable-shared
+ --enable-languages=c,c++
+ --enable-seh-exceptions
+ --enable-threads=posix
+ --enable-tls
+ --disable-nls
+ --disable-shared
  --enable-static
- --enable-threads=mcf
- --enable-graphite
  --enable-fully-dynamic-string
- --enable-libstdcxx-time=yes
- --disable-libstdcxx-pch
- --disable-libstdcxx-debug
- --disable-isl-version-check
  --enable-lto
+ --enable-plugins
  --enable-libgomp
- --disable-multilib
- --enable-checking=release
- --disable-rpath
+ --with-dwarf2
  --disable-win32-registry
- --enable-nls
- --disable-werror
- --disable-symvers
- --with-libiconv
- --with-system-zlib
- --with-gmp=/mingw64
- --with-mpfr=/mingw64
- --with-mpc=/mingw64
- --with-isl=/mingw64
- --with-pkgversion='gcc-7-branch HEAD with MCF thread model, built by
LH_Mouse.'
- --with-bugurl=https://gcc-mcf.lhmouse.com/
- --with-gnu-as
- --with-gnu-ld
- --disable-tls
-Thread model: mcf
-gcc version 7.2.1 20171119 (gcc-7-branch HEAD with MCF thread model, built by
LH_Mouse.)
+ --enable-version-specific-runtime-libs
+ --prefix=/mingw64-64
+ --with-sysroot=/mingw64-64
+ --target=x86_64-w64-mingw32
+ --enable-targets=all
+ --enable-checking=release
+ --with-gmp=/usr/new-gcc/lib/gmp-5.0.5
+ --with-mpfr=/usr/new-gcc/lib/mpfr-2.4.2
+ --with-mpc=/usr/new-gcc/lib/mpc-0.9
+ --with-isl=/usr/new-gcc/lib/isl-0.18
+ --with-cloog=/usr/new-gcc/lib/cloog-0.18.4
+ --with-host-libstdcxx='-lstdc++ -lsupc++'
+ --disable-cloog-version-check
+ --enable-cloog-backend=isl
+Thread model: posix
+gcc version 7.1.0 (GCC)

E:\Desktop>
```

I notice that:
0) You didn't specify `--build=`.
1) You specified `--enable-targets=all` but I think this does not affect mingw
targets according to <https://gcc.gnu.org/install/configure.html> and should be
removed.

Maybe you should try adding `--build=`?