testsuite: Add missing #include on <stdlib.h>

This otherwise fails on newer Clangs, which warn
more aggressively on undeclared symbols.
24 jobs for master in 410 minutes and 19 seconds (queued for 13 minutes and 2 seconds)
Status Job ID Name Coverage
  Tool Lint
passed #473118
lint
lint-linters

00:00:16

failed #473121
lint allowed to fail
lint-submods

00:00:15

passed #473122
lint
lint-submods-branch

00:00:25

passed #473119
lint
lint-testsuite

00:00:17

passed #473120
lint
typecheck-testsuite

00:00:20

 
  Quick Build
passed #473123
x86_64-linux
hadrian-ghc-in-ghci

00:10:39

 
  Lint
passed #473124
lint
lint-base

00:17:54

 
  Build
passed #473125
x86_64-linux
stack-hadrian-build

00:10:44

passed #473126
x86_64-linux
validate-x86_64-linux-deb9-hadrian

01:56:56

 
  Full Build
failed #473129
aarch64-linux allowed to fail
validate-aarch64-linux-deb10

00:19:38

failed #473130
armv7-linux allowed to fail
validate-armv7-linux-deb10

00:19:31

passed #473131
x86_64-linux
validate-i386-linux-deb9

01:40:22

passed #473128
x86_64-darwin
validate-x86_64-darwin

01:10:25

passed #473132
x86_64-linux
validate-x86_64-linux-deb9-debug

01:57:38

passed #473134
x86_64-linux
validate-x86_64-linux-deb9-dwarf

02:09:10

passed #473133
x86_64-linux
validate-x86_64-linux-deb9-integer-simple

01:36:52

passed #473127
x86_64-linux
validate-x86_64-linux-deb9-unreg-hadrian

03:20:59

passed #473135
x86_64-linux
validate-x86_64-linux-fedora27

01:50:37

failed #473136
new-x86_64-windows test allowed to fail
validate-x86_64-windows-hadrian

00:05:40

 
  Packaging
failed #473137
x86_64-linux allowed to fail
doc-tarball

00:00:27

 
  Testing
manual #473138
x86_64-linux allowed to fail manual
hackage
passed #473140
x86_64-linux-perf
perf

00:07:12

passed #473139
x86_64-linux
perf-nofib

00:38:55

 
  Deploy
failed #473141
x86_64-linux allowed to fail
pages

00:00:13

 
Name Stage Failure
failed
lint-submods Tool Lint
Entering 'libraries/unix'
Entering 'libraries/xhtml'
Entering 'nofib'
Entering 'utils/haddock'
Entering 'utils/hsc2hs'
Authenticating with credentials from job payload (GitLab Registry)
$ git fetch "$CI_MERGE_REQUEST_PROJECT_URL" $CI_MERGE_REQUEST_TARGET_BRANCH_NAME
fatal: no path specified; see 'git help pull' for valid url syntax
ERROR: Job failed: exit code 1
failed
pages Deploy
Entering 'nofib'
Entering 'utils/haddock'
Entering 'utils/hsc2hs'
Executing "step_script" stage of the job script
$ mkdir -p public/doc
$ tar -xf haddock.html.tar.xz -C public/doc
tar: haddock.html.tar.xz: Cannot open: No such file or directory
tar: Error is not recoverable: exiting now
ERROR: Job failed: exit code 1
failed
doc-tarball Packaging
Entering 'utils/haddock'
Entering 'utils/hsc2hs'
Downloading artifacts
Downloading artifacts for validate-x86_64-linux-deb9-debug (473132)...
Downloading artifacts from coordinator... ok
id=473132 responseStatus=200 OK token=3dkVZcRx
Executing "step_script" stage of the job script
$ if [ ! -f "$LINUX_BINDIST" ]; then # collapsed multi-line command
Error: ghc-x86_64-mingw32.tar.xz does not exist. Did the 64-bit Windows job fail?
ERROR: Job failed: exit code 1
failed
validate-x86_64-windows-hadrian Full Build
Git branch:   13-1-stable
GO version: go1.13.8
Built: 2020-06-19T21:12:23+0000
OS/Arch: windows/amd64
Uploading artifacts...
Runtime platform
arch=amd64 os=windows pid=2740 revision=6214287e version=13.1.0
WARNING: junit.xml: no matching files
ERROR: No files to upload
ERROR: Job failed: exit status 1
failed
validate-aarch64-linux-deb10 Full Build
Uploading artifacts...
WARNING: ghc-aarch64-linux-deb10.tar.xz: no matching files
WARNING: junit.xml: no matching files
WARNING: performance-metrics.tsv: no matching files
ERROR: No files to upload
Uploading artifacts...
WARNING: junit.xml: no matching files
ERROR: No files to upload
ERROR: Job failed: exit code 1
failed
validate-armv7-linux-deb10 Full Build
Uploading artifacts...
WARNING: ghc-armv7-linux-deb10.tar.xz: no matching files
WARNING: junit.xml: no matching files
WARNING: performance-metrics.tsv: no matching files
ERROR: No files to upload
Uploading artifacts...
WARNING: junit.xml: no matching files
ERROR: No files to upload
ERROR: Job failed: exit code 1