NotificationsYou must be signed in to change notification settings
Fork2.5k
Star10k

cli: fix undefined alloca() on CYGWIN#7022

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to ourterms of service andprivacy statement. We’ll occasionally send you account related emails.

Already on GitHub?Sign in to your account

Jump to bottom

Merged

ethomson merged 1 commit intolibgit2:mainfromcarlo-bramini:fix-cygwin-1

Jan 20, 2025

Merged

cli: fix undefined alloca() on CYGWIN#7022

ethomson merged 1 commit intolibgit2:mainfromcarlo-bramini:fix-cygwin-1

Jan 20, 2025

Conversation

Copy link

Contributor

carlo-bramini commentedJan 20, 2025

I tried to build my libgit2-1.9.0 package for CYGWIN but I got an error.
This message appears when compiling:

[199/671] Building C object src/cli/CMakeFiles/git2_cli.dir/opt.c.o libgit2-1.9.0/src/cli/opt.c:In function ‘cli_opt_parse’: libgit2-1.9.0/src/cli/opt.c:564:23: warning: implicit declaration of function ‘alloca’; did you mean ‘malloc’? [-Wimplicit-function-declaration]  564 |         given_specs = alloca(sizeof(const cli_opt_spec *) * (args_len + 1));      |                       ^~~~~~      |                       malloc

and later the linker emits this error message:

[668/671] Linking C executable git2.exeFAILED: git2.exe/usr/x86_64-pc-cygwin/bin/ld: src/cli/CMakeFiles/git2_cli.dir/opt.c.o: in function `cli_opt_parse':/usr/src/debug/libgit2-1.9.0-1/src/cli/opt.c:564:(.text+0xce3): undefined reference to `alloca' collect2: error: ld returned 1 exit status

The error is fixed by addingalloca.h to included headers.
Hopefully,opt.c already allows to addalloca.h for some platforms, so I just added an additional test for the preprocessor for checking if the target is CYGWIN.

cli: fix undefined alloca() on CYGWIN

63cffe3

I tried to build my libgit2-1.9.0 package for CYGWIN but I got an error. This message appears when compiling:[199/671] Building C object src/cli/CMakeFiles/git2_cli.dir/opt.c.olibgit2-1.9.0/src/cli/opt.c: In function ‘cli_opt_parse’:libgit2-1.9.0/src/cli/opt.c:564:23: warning: implicit declaration of function ‘alloca’; did you mean ‘malloc’? [-Wimplicit-function-declaration]  564 |         given_specs = alloca(sizeof(const cli_opt_spec *) * (args_len + 1));      |                       ^~~~~~      |                       mallocand later the linker emits this error message:[668/671] Linking C executable git2.exeFAILED: git2.exe/usr/x86_64-pc-cygwin/bin/ld: src/cli/CMakeFiles/git2_cli.dir/opt.c.o: in function `cli_opt_parse':/usr/src/debug/libgit2-1.9.0-1/src/cli/opt.c:564:(.text+0xce3): undefined reference to `alloca'collect2: error: ld returned 1 exit statusThe error is fixed by adding alloca.h to included headers.Hopefully, opt.c already allows to add alloca.h for some platforms, so I just added an additional test for the preprocessor for checking if the target is CYGWIN.