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Implicit int error when using with Clang

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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
55/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Stale
Tech stack
c
Domain
build-system

Research direction

Start by comparing the flink.c probe command in configure and configure.ac, then reproduce the configuration with amdclang on an OLCF machine if available. Verify that the updated probe completes without implicit-int or undeclared-function errors and that the generated configure behavior remains consistent.

Written by the indexing model from the issue text.

Description

When configuring using amdclang on OLCF machines, I get:

configure: flink.c:1:1: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]
main(){ FF(); return 0; }
^
int
flink.c:1:9: error: call to undeclared function 'f_fun'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
main(){ FF(); return 0; }
        ^
<command line>:1:12: note: expanded from here
#define FF f_fun
           ^
2 errors generated.
configure: error: giving up

which can be remedied by changing

echo "main(){ FF(); return 0; }" > flink.c

to

echo "int main(){ int FF(); return 0; }" > flink.c

in configure and configure.ac

Any reason not to?

Dominant language
C
Stars
112
Forks
35
PR merge metrics
No merged PRs in 30d

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