[PATCH] oss-fuzz: move linker arg to fix coverage-build

[Alexander Bulekov]

The order of the add_project_link_arguments calls impacts which
arguments are placed between --start-group and --end-group.
OSS-Fuzz coverage builds seem to just add these to CFLAGS:
-fprofile-instr-generate -fcoverage-mapping pthread -Wl,--no-as-needed
--Wl,-ldl -Wl,-lm Wno-unused-command-line-argument

for some reason that is enough to shift the fork_fuzz.ld linker-script
back into the linker group. Move the linker-script meson call before the
other calls to mitigate this.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
---
 meson.build | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

Good news! Standard oss-fuzz builds are working again:
https://oss-fuzz-build-logs.storage.googleapis.com/log-2fa5122f-c98c-4e46-b3ff-e6835d9ecda6.txt

Bad news: Coverage builds are still-broken:
https://oss-fuzz-build-logs.storage.googleapis.com/log-dafece55-81f2-4d1d-a686-c5197cdd15c1.txt

For some reason, just switching around the order of the
add_project_arguments fixes this (i.e. the order of the calls impacts
which arguments are placed between --start-group --end-group). I don't
really like this because it makes this linker-script block even more
visible in meson.build, by placing it directly beneath the "Compiler
flags" heading. Paolo, do you have a better suggestion?

diff --git a/meson.build b/meson.build
index 5421eca66a..2ba1823ca3 100644
--- a/meson.build
+++ b/meson.build
@@ -49,6 +49,14 @@ configure_file(input: files('scripts/ninjatool.py'),
 # Compiler flags #
 ##################
 
+# Specify linker-script with add_project_link_arguments so that it is not 
placed
+# within a linker --start-group/--end-group pair
+if 'CONFIG_FUZZ' in config_host
+   add_project_link_arguments(['-Wl,-T,',
+                               (meson.current_source_dir() / 
'tests/qtest/fuzz/fork_fuzz.ld')],
+                              native: false, language: ['c', 'cpp', 'objc'])
+endif
+
 add_project_arguments(config_host['QEMU_CFLAGS'].split(),
                       native: false, language: ['c', 'objc'])
 add_project_arguments(config_host['QEMU_CXXFLAGS'].split(),
@@ -58,13 +66,6 @@ 
add_project_link_arguments(config_host['QEMU_LDFLAGS'].split(),
 add_project_arguments(config_host['QEMU_INCLUDES'].split(),
                       language: ['c', 'cpp', 'objc'])
 
-# Specify linker-script with add_project_link_arguments so that it is not 
placed
-# within a linker --start-group/--end-group pair
-if 'CONFIG_FUZZ' in config_host
-   add_project_link_arguments(['-Wl,-T,',
-                               (meson.current_source_dir() / 
'tests/qtest/fuzz/fork_fuzz.ld')],
-                              native: false, language: ['c', 'cpp', 'objc'])
-endif
 
 link_language = meson.get_external_property('link_language', 'cpp')
 if link_language == 'cpp'
-- 
2.28.0