[igraph] igraph_read_graph_gml memory leak?

[Mile Sikic]

Dear sirs

I am analyzing memory allocation by Valgrind. 

When I use gml input parser i get the following output

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HEAP SUMMARY:

==3800==     in use at exit: 16,458 bytes in 3 blocks

==3800==   total heap usage: 228,595 allocs, 228,592 frees, 7,470,226 bytes allocated

==3800== 

==3800== 8 bytes in 1 blocks are still reachable in loss record 1 of 3

==3800==    at 0x4C274A8: malloc (vg_replace_malloc.c:236)

==3800==    by 0x4EB9A4F: igraph_gml_yyensure_buffer_stack (foreign-gml-lexer.c:1528)

==3800==    by 0x4EBA72A: igraph_gml_yylex (foreign-gml-lexer.c:765)

==3800==    by 0x4EB93C1: igraph_gml_yyparse (foreign-gml-parser.c:1368)

==3800==    by 0x4EA8EC3: igraph_read_graph_gml (foreign.c:1095)

==3800==    by 0x41026B: init_infected_structure(input*, SIMULATION, infected*) (epidemic.cpp:1023)

==3800==    by 0x40D348: run_simulation(int, char**, SIMULATION) (epidemic.cpp:41)

==3800==    by 0x416161: main (main.cpp:48)

==3800== 

==3800== 64 bytes in 1 blocks are still reachable in loss record 2 of 3

==3800==    at 0x4C274A8: malloc (vg_replace_malloc.c:236)

==3800==    by 0x4EB9ED2: igraph_gml_yy_create_buffer (foreign-gml-lexer.c:1364)

==3800==    by 0x4EBA749: igraph_gml_yylex (foreign-gml-lexer.c:767)

==3800==    by 0x4EB93C1: igraph_gml_yyparse (foreign-gml-parser.c:1368)

==3800==    by 0x4EA8EC3: igraph_read_graph_gml (foreign.c:1095)

==3800==    by 0x41026B: init_infected_structure(input*, SIMULATION, infected*) (epidemic.cpp:1023)

==3800==    by 0x40D348: run_simulation(int, char**, SIMULATION) (epidemic.cpp:41)

==3800==    by 0x416161: main (main.cpp:48)

==3800== 

==3800== 16,386 bytes in 1 blocks are still reachable in loss record 3 of 3

==3800==    at 0x4C274A8: malloc (vg_replace_malloc.c:236)

==3800==    by 0x4EB9EEB: igraph_gml_yy_create_buffer (foreign-gml-lexer.c:1373)

==3800==    by 0x4EBA749: igraph_gml_yylex (foreign-gml-lexer.c:767)

==3800==    by 0x4EB93C1: igraph_gml_yyparse (foreign-gml-parser.c:1368)

==3800==    by 0x4EA8EC3: igraph_read_graph_gml (foreign.c:1095)

==3800==    by 0x41026B: init_infected_structure(input*, SIMULATION, infected*) (epidemic.cpp:1023)

==3800==    by 0x40D348: run_simulation(int, char**, SIMULATION) (epidemic.cpp:41)

==3800==    by 0x416161: main (main.cpp:48)

==3800== 

==3800== LEAK SUMMARY:

==3800==    definitely lost: 0 bytes in 0 blocks

==3800==    indirectly lost: 0 bytes in 0 blocks

==3800==      possibly lost: 0 bytes in 0 blocks

==3800==    still reachable: 16,458 bytes in 3 blocks

==3800==         suppressed: 0 bytes in 0 blocks

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If I use edgelist format i get

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 HEAP SUMMARY:

==3996==     in use at exit: 0 bytes in 0 blocks

==3996==   total heap usage: 21,527 allocs, 21,527 frees, 3,161,957 bytes allocated

==3996== 

==3996== All heap blocks were freed -- no leaks are possible

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I believe the reason for that is a memory leak in gml parser

Regards

Mile SIkic