Semantic errors

Hello to all,
I'm browsins git code with Eclipse. I'm on a local branch called
"studio" based on master (last public commit e902e9b by Junio C Hamano
on Monday March 11 2019). I've built everything by changing:
CFLAGS = -g -Wall (removing -O2 to have smooth trace in debugging).
But the environment detects the following semantic errors (I made no
edits!!!):
Description	Resource	Path	Location	Type
Symbol 'GIT_HTML_PATH' could not be resolved	git.c	/git	
line 154	Semantic Error
Symbol 'GIT_MAN_PATH' could not be resolved	git.c	/git	
line 158	Semantic Error
Symbol 'GIT_INFO_PATH' could not be resolved	git.c	/git	
line 162	Semantic Error
Symbol 'active_cache' could not be resolved	commit.c	/git
/builtin	line 899	Semantic Error
Field 'ce_intent_to_add(active_cache[i])' could not be resolved	
commit.c	/git/builtin	line 899	Semantic Error
Symbol 'active_nr' could not be resolved	commit.c	/git/bu
iltin	line 889	Semantic Error
Symbol 'active_nr' could not be resolved	commit.c	/git/bu
iltin	line 898	Semantic Error
Field 'oid' could not be resolved	commit.c	/git/builtin	
line 1654	Semantic Error
Symbol 'active_nr' could not be resolved	commit.c	/git/bu
iltin	line 901	Semantic Error
Symbol 'active_cache_tree' could not be resolved	commit.c	
/git/builtin	line 1654	Semantic Error
Symbol 'active_cache_changed' could not be resolved	commit.c	
/git/builtin	line 418	Semantic Error
Symbol 'active_cache_tree' could not be resolved	commit.c	
/git/builtin	line 419	Semantic Error
Symbol 'active_nr' could not be resolved	commit.c	/git/bu
iltin	line 254	Semantic Error
Symbol 'active_cache' could not be resolved	commit.c	/git
/builtin	line 255	Semantic Error

I can debug without problems, but what if I should trece through one of
those errors?
How can I fix them?
Thanks in advance!!!
Fabio.