What version of Go are you using (go version)?

$ go version
go version go1.15.3 windows/amd64

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

$ go env
set GO111MODULE=
set GOARCH=amd64
set GOBIN=
set GOCACHE=C:\Users\nguyenha\AppData\Local\go-build
set GOENV=C:\Users\nguyenha\AppData\Roaming\go\env
set GOEXE=.exe
set GOFLAGS=
set GOHOSTARCH=amd64
set GOHOSTOS=windows
set GOINSECURE=
set GOMODCACHE=C:\Users\nguyenha\go\pkg\mod
set GONOPROXY=
set GONOSUMDB=
set GOOS=windows
set GOPATH=C:\Users\nguyenha\go
set GOPRIVATE=
set GOPROXY=https://proxy.golang.org,direct
set GOROOT=c:\go
set GOSUMDB=sum.golang.org
set GOTMPDIR=
set GOTOOLDIR=c:\go\pkg\tool\windows_amd64
set GCCGO=gccgo
set AR=ar
set CC=gcc
set CXX=g++
set CGO_ENABLED=1
set GOMOD=D:\work\projects\mimic\mimic-core\go.mod
set CGO_CFLAGS=-g -O2
set CGO_CPPFLAGS=
set CGO_CXXFLAGS=-g -O2
set CGO_FFLAGS=-g -O2
set CGO_LDFLAGS=-g -O2
set PKG_CONFIG=pkg-config
set GOGCCFLAGS=-m64 -mthreads -fmessage-length=0 -fdebug-prefix-map=C:\Users\nguyenha\AppData\Local\Temp\go-build611343782=/tmp/go-build -gno-record-gcc-switches

What did you do?

set CGO_ENABLED=1
set CC=clang
set PATH=C:\Program Files\mingw-w64\x86_64-8.1.0-posix-seh-rt_v6-rev0\mingw64\bin;%PATH%
go build -buildmode=c-shared -o bin/crawler.dll -ldflags "-v" -v my/pathp/export

What did you expect to see?

Build success.

What did you see instead?

HEADER = -H10 -T0xffffffffffffffff -R0xffffffff
pclntab=1272164 bytes, funcdata total 320301 bytes
symsize = 0
host link: "clang" "-m64" "-mconsole" "-Wl,--tsaware" "-Wl,--nxcompat" "-Wl,--major-os-version=6" "-Wl,--minor-os-version=1" "-Wl,--major-subsystem-version=6" "-Wl,--minor-subsystem-version=1" "-Wl,-Bsymbolic" "-shared" "-o" "crawler.dll" "-Qunused-arguments" "C:\Users\nguyenha\AppData\Local\Temp\go-link-077327015\go.o" "C:\Users\nguyenha\AppData\Local\Temp\go-link-077327015\000000.o" "C:\Users\nguyenha\AppData\Local\Temp\go-link-077327015\000001.o" "C:\Users\nguyenha\AppData\Local\Temp\go-link-077327015\000002.o" "C:\Users\nguyenha\AppData\Local\Temp\go-link-077327015\000003.o" "C:\Users\nguyenha\AppData\Local\Temp\go-link-077327015\000004.o" "C:\Users\nguyenha\AppData\Local\Temp\go-link-077327015\000005.o" "C:\Users\nguyenha\AppData\Local\Temp\go-link-077327015\000006.o" "C:\Users\nguyenha\AppData\Local\Temp\go-link-077327015\000007.o" "C:\Users\nguyenha\AppData\Local\Temp\go-link-077327015\000008.o" "-g" "-O2" "-g" "-O2" "-Wl,-T,C:\Users\nguyenha\AppData\Local\Temp\go-link-077327015\fix_debug_gdb_scripts.ld" "-Wl,--start-group" "-lmingwex" "-lmingw32" "-Wl,--end-group" "-lkernel32"
c:\go\pkg\tool\windows_amd64\link.exe: running clang failed: exit status 1104
LINK : warning LNK4044: unrecognized option '/-tsaware'; ignored
LINK : warning LNK4044: unrecognized option '/-nxcompat'; ignored
LINK : warning LNK4044: unrecognized option '/-major-os-version=6'; ignored
LINK : warning LNK4044: unrecognized option '/-minor-os-version=1'; ignored
LINK : warning LNK4044: unrecognized option '/-major-subsystem-version=6'; ignored
LINK : warning LNK4044: unrecognized option '/-minor-subsystem-version=1'; ignored
LINK : warning LNK4044: unrecognized option '/Bsymbolic'; ignored
LINK : warning LNK4044: unrecognized option '/T'; ignored
LINK : warning LNK4044: unrecognized option '/-start-group'; ignored
LINK : warning LNK4044: unrecognized option '/-end-group'; ignored
LINK : fatal error LNK1104: cannot open file 'mingwex.lib'
clang: error: linker command failed with exit code 1104 (use -v to see invocation)